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l2 vfi manual through loopback PA-MC-8TE1 +
port adapter
• l2 vfi manual, page 3
• l2protocol-tunnel, page 5
• l2protocol-tunnel cos, page 8
• l2protocol-tunnel drop-threshold, page 10
• l2protocol-tunnel global drop-threshold, page 12
• l2protocol-tunnel point-to-point, page 14
• l2protocol-tunnel shutdown-threshold, page 15
• l3vpn encapsulation ip, page 17
• lacp active-port distribution automatic, page 18
• lacp fast-switchover, page 20
• lacp max-bundle, page 22
• lacp port-priority, page 24
• lacp rate, page 26
• lacp system-priority, page 28
• lbo, page 30
• lex burned-in-address, page 32
• lex input-address-list, page 33
• lex input-type-list, page 35
• lex priority-group, page 37
• lex retry-count, page 39
• lex timeout, page 40
• linecard-group y-cable, page 41
• linecode, page 43
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• line-mode, page 44
• line-rate, page 46
• line-term, page 49
• line-termination, page 51
• link debounce, page 53
• link state group, page 55
• link state track, page 57
• li-slot rp rate, page 58
• link-test, page 59
• load-balancing, page 60
• load-interval, page 62
• local ip address, page 64
• local udp port, page 66
• local-lnm, page 67
• logging event, page 68
• logging source-interface, page 70
• logging event link-status (global configuration), page 72
• logging event link-status (interface configuration), page 74
• logging event subif-link-status, page 75
• logging-events, page 77
• logging-events (T1-E1 controller), page 78
• loopback (CEM), page 79
• loopback (DSL controller), page 81
• loopback (E3 controller), page 84
• loopback (interface), page 86
• loopback (J1 controller ), page 88
• loopback (PA-MC-8TE1+ port adapter), page 89
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l2 vfi manual
l2 vfi manual
To create a Layer 2 virtual forwarding instance (VFI) and enter Layer 2 VFI manual configuration mode, use
the l2vfimanual command in global configuration mode. To remove the Layer 2 VFI, use the no form of this
command.
l2 vfi name manual
no l2 vfi name manual
Syntax Description
name
Command Default
The Layer 2 VFI is not configured.
Command Modes
Global configuration (config)
Command History
Usage Guidelines
Name of a new or existing Layer 2 VFI .
Release
Modification
12.2(18)SXF
This command was introduced on the Supervisor Engine 720.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
15.0(1)M
This command was integrated into a release earlier than Cisco IOS
Release 15.0(1)M.
Cisco IOS XE Release 3.7S
This command was integrated into Cisco IOS XE Release 3.7S.
A VFI is a collection of data structures used by the data plane, software-based or hardware-based, to forward
packets to one or more virtual circuits (VC). It is populated and updated by both the control plane and the
data plane and also serves as the data structure interface between the control plane and the data plane.
Within the Layer 2 VFI manual configuration mode, you can configure the following parameters:
• VPN ID of a Virtual private LAN service (VPLS) domain
• Addresses of other PE routers in this domain
• Type of tunnel signaling and encapsulation mechanism for each peer
Within the Layer 2 VFI manual configuration mode, the following commands are available:
• vpn id vpn-id
• [no] neighborremote-router-id {encapsulation {l2tpv3 | mpls} | pw-classpw-name| no-split-horizon}
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l2 vfi manual
Examples
This example shows how to create a Layer 2 VFI, enter Layer 2 VFI manual configuration mode, and configure
a VPN ID:
Router(config)# l2 vfi vfitest1 manual
Router(config-vfi)# vpn id 303
Related Commands
Command
Description
l2 vfi point-to-point
Establishes a point-to-point Layer 2 VFI between two
separate networks.
vpn id
Configures a VPN ID in RFC 2685 format. You can
change the value of the VPN ID only after its
configuration, and you cannot remove it.
neighbor
Specifies the type of tunnel signaling and
encapsulation mechanism for each peer.
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l2protocol-tunnel
l2protocol-tunnel
To enable the protocol tunneling on an interface and specify the type of protocol to be tunneled, use the
l2protocol-tunnel command in global or interface configuration mode. To disable protocol tunneling, use
the no form of this command.
Global Configuration
l2protocol-tunnel [cos cos-value| global| mac-address]
no l2protocol-tunnel
Interface Configuration
l2protocol-tunnel [cdp| lldp| stp| vtp]
no l2protocol-tunnel
Syntax Description
cos cos-value
(Optional) Specifies a class of service (CoS) value
globally on all ingress Layer 2 protocol tunneling
ports.
global
(Optional) Displays global settings.
mac-address
(Optional) Displays L2PT MAC address.
cdp
(Optional) Enables Cisco Discovery Protocol (CDP)
tunneling.
lldp
(Optional) Enables Link Layer Discovery Protocol
(LLDP) tunneling.
stp
(Optional) Enables Spanning Tree Protocol (STP)
tunneling.
vtp
(Optional) Enables VLAN Trunking Protocol (VTP)
tunneling.
Command Default
Disabled
Command Modes
Global configuration (config)
Interface configuration (config-if)
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l2protocol-tunnel
Command History
Usage Guidelines
Release
Modification
12.2(14)SX
Support for this command was introduced on the Supervisor Engine 720.
12.2(17d)SXB
Support for this command on the Supervisor Engine 2 was extended to
Release 12.2(17d)SXB.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
15.2(2)T
This command was modified. The lldp, cos, global, and mac-address
keywords were added.
On all the service provider edge switches, you must enable PortFast BPDU filtering on the 802.1Q tunnel
ports by entering these commands:
Router(config-if)# spanning-tree bpdufilter enable
Router(config-if)# spanning-tree portfast
Note
PortFast BPDU filtering is enabled automatically on tunnel ports.
If you do not specify a protocol, all protocols are tunneled.
You can configure protocol tunneling on VLAN and trunk interfaces.
You must enter the switchport command once without any keywords to configure the LAN port as a Layer
2 interface before you can enter additional switchport commands with keywords. This action is required only
if you have not entered the switchport command for the interface.
Examples
This example shows how to enable a tunneling protocol on an interface:
Router> enable
Router# configure terminal
Router#(config)interface FastEthernet 0/0
Router(config-if)# l2protocol-tunnel cdp
This example shows how to disable a tunneling protocol on an interface:
Router> enable
Router# configure terminal
Router#(config)interface fastEthernet 4/0
Router(config-if)# no l2protocol-tunnel
Protocol tunneling disabled on interface fastEthernet 4/1
Related Commands
Command
Description
show l2protocol-tunnel
Displays the protocols that are tunneled on an
interface or on all interfaces.
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l2protocol-tunnel
Command
Description
switchport
Modifies the switching characteristics of the Layer
2-switched interface.
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l2protocol-tunnel cos
l2protocol-tunnel cos
To specify a class of service (CoS) value globally on all ingress Layer-2 protocol tunneling ports, use the
l2protocol-tunnelcoscommand in global configuration mode. To return to the default , use the no form of
this command.
l2protocol-tunnel cos cos-value
no l2protocol-tunnel cos
Syntax Description
cos-value
Command Default
The cos-value is 5
Command Modes
Global configuration
Command History
Usage Guidelines
CoS value; valid values are from 0 to 7.
Release
Modification
12.2(14)SX
Support for this command was introduced on the Supervisor Engine 720.
12.2(17d)SXB
Support for this command on the Supervisor Engine 2 was extended to
Release 12.2(17d)SXB.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
The cos-value is the CoS value that you assign to the PDUs on a Layer 2-protocol tunnel port before tunneling
the PDUs through the service-provider network.
You can specify a CoS value globally on all ingress Layer 2-protocol tunneling ports. Because the CoS value
applies to all ingress tunneling ports, all encapsulated PDUs that are sent out by the Cisco 7600 series router
have the same CoS value.
On all the service-provider edge switches, you must enable PortFast BPDU filtering on the 802.1Q tunnel
ports by entering these commands:
Router(config-if)# spanning-tree bpdufilter enable
Router(config-if)# spanning-tree portfast
Note
PortFast BPDU filtering is enabled automatically on tunnel ports.
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l2protocol-tunnel cos
Examples
This example shows how to specify a CoS value on all ingress Layer 2-protocol tunneling ports:
Router(config)# l2protocol-tunnel cos 6
Router(config)#
Related Commands
Command
Description
show l2protocol-tunnel
Displays the protocols that are tunneled on an
interface or on all interfaces.
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l2protocol-tunnel drop-threshold
l2protocol-tunnel drop-threshold
To specify the maximum number of packets that can be processed for the specified protocol on that interface
before being dropped, use the l2protocol-tunneldrop-threshold command in interface configuration mode.
To reset all the threshold values to 0 and disable the drop threshold, use the no form of this command.
l2protocol-tunnel drop-threshold [cdp| stp| vtp] packets
no l2protocol-tunnel drop-threshold [cdp| stp| vtp]
Syntax Description
cdp
(Optional) Specifies CDP packets.
stp
(Optional) Specifies STP packets.
vtp
(Optional) Specifies VTP packets.
packets
Maximum number of packets; valid values are from
1 to 4096 packets.
Command Default
Disabled
Command Modes
Interface configuration
Command History
Usage Guidelines
Release
Modification
12.2(14)SX
Support for this command was introduced on the Supervisor Engine 720.
12.2(17d)SXB
Support for this command on the Supervisor Engine 2 was extended to
Release 12.2(17d)SXB.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
On all the service-provider edge switches, you must enable PortFast BPDU filtering on the 802.1Q tunnel
ports by entering these commands:
Router(config-if)# spanning-tree bpdufilter enable
Router(config-if)# spanning-tree portfast
Note
PortFast BPDU filtering is enabled automatically on tunnel ports.
If you do not specify a protocol, the threshold applies to all protocols.
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l2protocol-tunnel drop-threshold
You can configure protocol tunneling on switch ports only. You must enter the switchport command once
without any keywords to configure the LAN port as a Layer 2 interface before you can enter additional
switchport commands with keywords. This action is required only if you have not entered the switchport
command for the interface.
Refer to the “Configuring IEEE 802.1Q Tunneling and Layer 2 Protocol Tunneling” chapter of the Cisco 7600
Series Router Cisco IOS Software Configuration Guide for additional information on setting the drop threshold
value.
Examples
This example shows how to set the drop threshold:
Router(config-if)# switchport
Router(config-if)# l2protocol-tunnel drop-threshold 3000
Router(config-if)#
Related Commands
Command
Description
l2protocol-tunnel
Enables the protocol tunneling on an interface and
specifies the type of protocol to be tunneled.
l2protocol-tunnel cos
Specifies a CoS value globally on all ingress Layer-2
protocol tunneling ports.
l2protocol-tunnel global drop-threshold
Enables rate limiting at the software level.
l2protocol-tunnel shutdown-threshold
Specifies the maximum number of packets that can
be processed for the specified protocol on that
interface in 1 second.
show l2protocol-tunnel
Displays the protocols that are tunneled on an
interface or on all interfaces.
switchport
Modifies the switching characteristics of the Layer
2-switched interface.
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l2protocol-tunnel global drop-threshold
l2protocol-tunnel global drop-threshold
To enable rate limiting at the software level, use the l2protocol-tunnelglobaldrop-threshold command in
global configuration mode. To disable the software rate limiter on the Cisco 7600 series routers, use the no
form of this command.
l2protocol-tunnel global drop-threshold threshold
no l2protocol-tunnel global drop-threshold
Syntax Description
threshold
Maximum rate of incoming PDUs before excessive
PDUs are dropped; valid values are from 100 to 20000
PDUs.
Command Default
Global thresholds are not configured.
Command Modes
Global configuration
Command History
Usage Guidelines
Release
Modification
12.2(17a)SX
Support for this command was introduced on the Supervisor Engine
720.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
This command is not supported on Cisco 7600 series routers that are configured with a Supervisor Engine 2.
All three PDUs (normal BPDU, CDP, and VTP packets) that arrive on Layer 2-protocol tunnel-enabled ports
are rate limited. Rate limiting occurs in the ingress direction in Layer 2-protocol tunneling. If the rate of the
incoming PDUs exceeds the configured threshold , the excessive PDUs are dropped.
Examples
This example shows how to enable rate limiting globally:
Router(config)# l2protocol-tunnel global drop-threshold 3000
Router(config)#
Related Commands
Command
Description
l2protocol-tunnel
Enables the protocol tunneling on an interface and
specifies the type of protocol to be tunneled.
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l2protocol-tunnel global drop-threshold
Command
Description
l2protocol-tunnel cos
Specifies a CoS value globally on all ingress Layer-2
protocol tunneling ports.
l2protocol-tunnel drop-threshold
Specifies the maximum number of packets that can
be processed for the specified protocol on that
interface before being dropped.
l2protocol-tunnel shutdown-threshold
Specifies the maximum number of packets that can
be processed for the specified protocol on that
interface in 1 second.
show l2protocol-tunnel
Displays the protocols that are tunneled on an
interface or on all interfaces.
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l2protocol-tunnel point-to-point
l2protocol-tunnel point-to-point
To enable point-to-point protocol tunneling, use the l2protocol-tunnel point-to-point command in interface
configuration mode. To disable, use the no form of this command.
l2protocol-tunnel point-to-point [pagp| lacp| udld]
no l2protocol-tunnel point-to-point [pagp| lacp| udld]
Syntax Description
pagp
(Optional) Enables port aggregation on a
point-to-point protocol tunneling.
lacp
(Optional) Enables link aggregation on a
point-to-point protocol tunneling.
udld
(Optional) Enables a unidirectional link dectection
on a point-to-point protocol tunneling.
Command Default
If no keyword is selected, tunneling is enabled for all three protocols.
Command Modes
Interface configuration (config-if)
Command History
Release
Modification
15.2(2)T
This command was introduced.
Usage Guidelines
To avoid a network failure, make sure that the network is a point-to-point topology before you enable tunneling
for PAgP, LACP, or UDLD packets.
Examples
The following example shows how to enable link aggregation on a point-to-point protocol tunneling:
Router(config-if
)# l2protocol-tunnel point-to-point lacp
Related Commands
Command
Description
show l2protocol-tunnel
Displays the enabled protocols and their values.
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l2protocol-tunnel shutdown-threshold
l2protocol-tunnel shutdown-threshold
To specify the maximum number of packets that can be processed for the specified protocol on that interface
in 1 second, use the l2protocol-tunnelshutdown-thresholdcommand in interface configuration mode. To
reset all the threshold values to 0 and disable the shutdown threshold, use the no form ofthis command.
l2protocol-tunnel shutdown-threshold [cdp| stp| vtp] packets
no l2protocol-tunnel shutdown-threshold [cdp| stp| vtp] packets
Syntax Description
cdp
(Optional) Specifies CDP tunneling.
stp
(Optional) Specifies STP tunneling.
vtp
(Optional) Specifies VTP tunneling.
packets
Shutdown threshold; valid values are from 1 to 4096.
Command Default
This command has no default settings.
Command Modes
Interface configuration
Command History
Usage Guidelines
Release
Modification
12.2(14)SX
Support for this command was introduced on the Supervisor Engine 720.
12.2(17d)SXB
Support for this command on the Supervisor Engine 2 was extended to
Release 12.2(17d)SXB.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
When the number of packets is exceeded, the port is put in error-disabled state.
On all the service-provider edge switches, you must enable PortFast BPDU filtering on the 802.1Q tunnel
ports by entering these commands:
Router(config-if)# spanning-tree bpdufilter enable
Router(config-if)# spanning-tree portfast
Note
PortFast BPDU filtering is enabled automatically on tunnel ports.
If you do not specify a protocol, the packets value applies to all protocols.
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l2protocol-tunnel shutdown-threshold
You can configure protocol tunneling on switch ports only. You must enter the switchport command once
without any keywords to configure the LAN port as a Layer 2 interface before you can enter additional
switchport commands with keywords. This action is required only if you have not entered the switchport
command for the interface.
Refer to the “Configuring IEEE 802.1Q Tunneling and Layer 2 Protocol Tunneling” chapter of the Cisco 7600
Series Router Cisco IOS Software Configuration Guide for additional information on setting the drop threshold
value.
Examples
This example shows how to specify the maximum number of CDP packets that can be processed on that
interface in 1 second:
Router(config-if)# switchport
Router(config-if)# l2protocol-tunnel shutdown-threshold cdp 200
Router(config-if)#
Related Commands
Command
Description
l2protocol-tunnel
Enables the protocol tunneling on an interface and
specifies the type of protocol to be tunneled.
show l2protocol-tunnel
Displays the protocols that are tunneled on an
interface or on all interfaces.
switchport
Modifies the switching characteristics of the Layer
2-switched interface.
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l3vpn encapsulation ip
l3vpn encapsulation ip
To configure an L3VPN encapsulation profile, use the l3vpnencapsulationip command in global configuration
mode. To remove the encapsulation profile, use the no form of this command.
l3vpn encapsulation ip profile name
no l3vpn encapsulation ip profile name
Syntax Description
profile name
Name of the Layer 3 encapsulation profile.
Command Default
The L3VPN encapsulation profile is not configured.
Command Modes
Global configuration (config)
Command History
Release
Modification
12.2(33)SRE
This command was introduced.
Usage Guidelines
When you use the l3vpnencapsulationip command you enter into L3VPN encapsulation configuration mode.
You can then specify the transport source mode and interface using thetransportipv4 command, set the GRE
key using the protocolgre command, and configure the L3VPN encapsulation profile.
Examples
The following example shows how to configure an L3VPN encapsulation profile:
Router(config)# l3vpn encapsulation ip tunnelencap
Related Commands
Command
Description
show l3vpn encapsulation ip
Displays the profile health and the underlying tunnel
interface.
transport ipv4
Specifies IPv4 transport source mode and the transport
source interface.
protocol gre
Specifies GRE as the tunnel mode and sets the GRE
key.
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lacp active-port distribution automatic
lacp active-port distribution automatic
To have an effective auto interleaved port priority distribution of active and bundled ports across different
slots that are part of the same port channel distributed EtherChannel (DEC) and multichassis EtherChannel
(MEC), use the lacp active-port distribution automaticcommand in port channel configuration mode.
lacp active-port distribution automatic
no lacp active-port distribution automatic
Syntax Description
This command has no keywords or arguments.
Command Default
Auto interleaved port priority is disabled.
Command Modes
Interface configuration (config-if)
Command History
Usage Guidelines
Release
Modification
12.2(33)SXI4
This command was introduced.
The auto interleaved port-priority feature automatically distributes active and bundled ports based on the
position of a port link when it comes up and is effective only if you configure it on the system that has the
higher LACP system priority.
The port priority per port that you configured continues to take precedence over a dynamic port number. You
need to perform a shutdown and no shutdown on the interface port channel to enable the auto interleaved port
priority feature on all ports.
Examples
This example shows how to configure interleaved port priority:
Router(config)# interface port23
Router(config-if)# lacp active-port distribution automatic
Please shut/no shut the port-channel for configuration to take effect immediately.
Router(config-if)# shutdown
Router(config-if)# no shutdown
Router(config-if)# end
This example shows how to verify that interleaved port priority is configured:
Router# show running interface port23
Building configuration...
Current configuration : 81 bytes
!
interface Port-channel23
no switchport
no ip address
lacp max-bundle 4
lacp active-port distribution automatic
end
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lacp active-port distribution automatic
Router# show etherchannel 23 summary
Flags: D - down P - bundled in port-channel
I - stand-alone s - suspended
H - Hot-standby (LACP only)
R - Layer3 S - Layer2
U - in use N - not in use, no aggregation
f - failed to allocate aggregator
M - not in use, no aggregation due to minimum links not met
m - not in use, port not aggregated due to minimum links not met
u - unsuitable for bundling
d - default port
w - waiting to be aggregated
Number of channel-groups in use: 9
Number of aggregators: 9
Group
Port-channel Protocol
Ports
------+-------------+-----------+----------------------------------------------23
Po23(RU)
LACP
Gi1/1/21(P) Gi1/1/22(P) Gi1/1/23(P)
Gi1/1/24(P) Gi2/1/17(H) Gi2/1/18(H)
Gi2/1/19(H) Gi2/1/20(H)
Last applied Hash Distribution Algorithm: Fixed
Note
Related Commands
The four active and bundled ports are from the same chassis and slot.
Command
Description
show etherchannel
Displays EtherChannel information for a port channel.
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lacp fast-switchover
lacp fast-switchover
To enable Link Aggregation Control Protocol (LACP) 1:1 link redundancy, use the lacp fast-switchover
command in interface configuration mode. To dis able LACP 1:1 link redundancy, use the no form of this
command.
lacp fast-switchover
no lacp fast-switchover
Syntax Description
This command has no arguments or keywords.
Command Default
LACP 1:1 link redundancy is disabled by default.
Command Modes
Interface configuration (config-if)
Command History
Usage Guidelines
Release
Modification
12.2(33)SXH
This command was introduced.
12.2(33)SRC
This command was integrated into Cisco IOS Release 12.2(33)SRC.
12.2(33)SB
Support for this command was implemented on the Cisco 10000 series
router and integrated into Cisco IOS Release 12.2(33)SB. The time allowed
for a link switchover was modified from the default of 2 seconds to 250
milliseconds.
Cisco IOS XE Release 2.5
This command was integrated into Cisco IOS XE Release 2.5
Prior to entering the lacp fast-switchover command, you must ensure the following:
• The port channel protocol type is LACP.
• The lacp max-bundle 1command has been entered on the port channel. The lacp fast-switchover
command will not affect the lacp max-bundle command.
When you enable LACP 1:1 link redundancy, based on the system priority and port priority, the port with the
higher system priority chooses the link as the active link and the other link as the standby link. When the
active link fails, the standby link is selected as the new active link without taking down the port channel.
When the original active link recovers, it reverts to its active link status. During this change-over, the port
channel is also up.
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lacp fast-switchover
Note
We recommend that you configure two ports only (one active and one hot-standby) in the bundle for
optimum performance.
You can enter this command on any port channels with different EtherChannel protocol types of LACP, Port
Aggregation Protocol (PAgP), or Fast EtherChannel (FEC).
Examples
This example shows how to enable LACP 1:1 link redundancy:
Router(config-if)# lacp fast-switchover
This example shows how to disable LACP 1:1 link redundancy:
Router(config-if)# no lacp fast-switchover
Related Commands
Command
Description
lacp max-bundle
Assigns and configures an EtherChannel interface to
an EtherChannel group.
show etherchannel
Displays the EtherChannel information for a channel.
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lacp max-bundle
lacp max-bundle
To define the maximum number of active bundled Link Aggregation Control Protocol (LACP) ports allowed
in a port channel, use the lacp max-bundle command in interface configuration mode. To return to the default
settings, use the no form of this command.
lacp max-bundle max-bundles
no lacp max-bundle
Syntax Description
max-bundles
Maximum number of active bundled ports allowed
in the port channel. Valid values are from 1 to 8. On
the Cisco ASR 1000 series router, valid values are 1
to 4.
The default settings are as follows:
• Maximum of 8 bundled ports per port channel.
• Maximum of 8 bundled ports and 8 hot-standby
ports per port channel if the port channels on
both sides of the LACP bundle are configured
in the same way.
• On the Cisco 10000 series router, maximum of
8 bundled ports per port channel.
Command Default
A maximum number of active bundled ports is not configured.
Command Modes
Interface configuration (config-if)
Command History
Release
Modification
12.2(18)SXD
Support for this command was introduced on the Supervisor Engine 720.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2(31)SB2
Support for this command was implemented on the Cisco 10000 series
router and integrated into Cisco IOS Release 12.2(31)SB2.
12.2(33)SRB
Support for this command on the Cisco 7600 router was integrated into
Cisco IOS Release 12.2(33)SRB.
12.2(33)SB
On the Cisco 10000 series router, the maximum number of bundled ports
per port channel was increased from 4 to 8.
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lacp max-bundle
Usage Guidelines
Release
Modification
Cisco IOS XE Release 2.4
This command was integrated into Cisco IOS XE Release 2.4.
12.2(33)SRE
This command was integrated into Cisco IOS Release 12.2(33)SRE.
The value specified in the max-bundles argument determines the number of active links that are bundled in
the port channel. The remaining links are in hot-standby mode.
On the Cisco 10000 series router, this command requires a Performance Routing Engine 2 (PRE2) or PRE3.
Examples
This example shows how to set 3 ports to bundle in port channel 2:
Router(config)# interface port-channel 2
Router(config-if)# lacp max-bundle 3
Router(config-if)#
Related Commands
Command
Description
interface port-channel
Creates a port-channel virtual interface and puts the
CLI in interface configuration mode.
ip address
Sets a primary or secondary IP address on an
interface.
show etherchannel
Displays the EtherChannel information for a channel.
show interfaces port-channel
Displays traffic that is seen by a specific port channel.
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lacp port-priority
lacp port-priority
To set the priority for a physical interface, use the lacp port-priority command in interface configuration
mode. To return to the default setting, use the no form of this command.
lacp port-priority priority
no lacp port-priority
Syntax Description
priority
Integer from 1 to 65535 that indicates the priority for
the physical interface. The default is 32768.
• On the Cisco ASR 1000 series router, the range
is 0 to 65535.
Command Default
The default port priority is set.
Command Modes
Interface configuration (config-if)
Command History
Release
Modification
12.1(13)EW
This command was introduced on the Cisco Catalyst 4500 series switches.
12.2(14)SX
Support for this command on the Supervisor Engine 720 was integrated
into Cisco IOS Release12.2(14)SX.
12.2(17d)SXB
Support for this command on the Supervisor Engine 2 was integrated into
Cisco IOS Release12.2(17d) SXB.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2(31)SB2
This command was integrated into Cisco IOS Release 12.2(31)SB2.
12.2(33)SRB
Support for this command on the Cisco 7600 router was integrated into
Cisco IOS Release 12.2(33)SRB.
Cisco IOS XE Release 2.4
This command was integrated into Cisco IOS XE Release 2.4.
15.1(2)SNG
This command was implemented on the Cisco ASR 901 Series Aggregation
Services Router.
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lacp port-priority
Usage Guidelines
Note
You may assign a port priority to each port on a device running Link Aggregation Control Protocol (LACP).
You can specify the port priority by using the lacp port-priority command at the command-line interface
(CLI) or use the default port priority (32768) that is carried as part of the LACP protocol data unit (PDU)
exchanged with the partner. Port priority is used to decide which ports should be put in standby mode when
a hardware limitation or the lacp max-bundle command configuration prevents all compatible ports from
aggregating. Priority is supported only on port channels with LACP-enabled physical interfaces.
A high priority number means a low priority.
Port priority together with port number form a port identifier.
To verify the configured port priority, issue the show lacp command.
Examples
This example shows how to set a priority of 23700 for an interface:
Device> enable
Device# configure terminal
Device(config)# interface ethernet0/0
Device(config-if)# lacp port-priority 23700
Device(config-if)#
Related Commands
Command
Description
channel-group
Assigns and configures an EtherChannel interface to
an EtherChannel group.
debug lacp
Enables debugging of LACP activities.
lacp max-bundle
Defines the maximum number of active bundled
LACP ports allowed in a port channel.
lacp system-priority
Sets the priority of the system.
show lacp
Displays information about LACP activity on the
device.
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lacp rate
lacp rate
To set the rate at which Link Aggregation Control Protocol (LACP) control packets are ingressed to an
LACP-supported interface, use the lacp rate command in interface configuration mode. To return to the
default settings, use the no form of this command.
lacp rate {normal| fast}
no lacp rate
Syntax Description
normal
Specifies that LACP control packets are ingressed at
the normal rate, every 30 seconds after the link is
bundled.
fast
Specifies that LACP control packets are ingressed at
the fast rate, once every 1 second.
Command Default
The default ingressed rate for control packets is 30 seconds after the link is bundled.
Command Modes
Interface configuration (config-if)
Command History
Usage Guidelines
Release
Modification
12.2(18)SXF2
This command was introduced on the Catalyst 6500 series switch.
12.2(33)SRC
This command was integrated into Cisco IOS Release 12.2(33)SRC.
Cisco IOS XE Release 3.6S
This command was implemented on Cisco ASR 1000 Series Aggregation
Services Routers in Cisco IOS XE Release 3.6S.
Use this command to modify the duration of a LACP timeout. The LACP timeout value is set on Cisco switches
to a value of 90 seconds. Using the lacp rate command, you can select the LACP timeout value for a switch
to be either 30 seconds or 1 second.
This command is supported only on LACP-enabled interfaces.
Examples
This example shows how to specify the fast (1-second) ingress rate on interface Ethernet 0/1:
Router(config)# interface ethernet 0/1
Router(config-if)# lacp rate fast
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lacp rate
Related Commands
Command
Description
show lacp
Displays LACP information.
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lacp system-priority
lacp system-priority
To set the priority for a system, use the lacp system-priority command in global configuration mode. To
return to the default setting, use the no form of this command.
lacp system-priority priority
no lacp system-priority
Syntax Description
priority
Integer from 1 to 65535 that indicates the priority for
the system. The default is 32768.
• On the Cisco ASR 1000 series router, the range
is 0 to 65535.
Command Default
The default system priority is set.
Command Modes
Global configuration (config)
Command History
Release
Modification
12.1(13)EW
This command was introduced on the Cisco Catalyst 4500 series switches.
12.2(14)SX
Support for this command on the Supervisor Engine 720 was integrated
into Cisco IOS Release12.2(14)SX.
12.2(17d)SXB
Support for this command on the Supervisor Engine 2 was integrated into
Cisco IOS Release12.2(17d) SXB.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2(31)SB2
This command was integrated into Cisco IOS Release 12.2(31)SB2.
12.2(33)SRB
Support for this command on the Cisco 7600 router was integrated into
Cisco IOS Release 12.2(33)SRB.
Cisco IOS XE Release 2.4
This command was integrated into Cisco IOS XE Release 2.4.
15.1(2)SNG
This command was implemented on the Cisco ASR 901 Series Aggregation
Services Router.
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lacp system-priority
Usage Guidelines
Note
You can assign a system priority to each device running Link Aggregation Control Protocol (LACP). You
can specify the system priority by using the lacp system-priority command at the command-line interface
(CLI) or use the default system priority (32768) that is carried as part of the LACP protocol data unit (PDU)
exchanged with the partner. System priority is used with the MAC address of the device to form the system
ID and also is used during negotiation with other systems. Priority is supported only on port channels with
LACP-enabled physical interfaces.
A high priority number means a low priority.
To verify the configured system priority, issue the show lacp command.
Examples
The following example shows how to set a system priority of 25500 for a device:
Router> enable
Router# configure terminal
Router(config)# lacp system-priority 25500
Related Commands
Command
Description
channel-group
Assigns and configures an EtherChannel interface to
an EtherChannel group.
debug lacp
Enables debugging of LACP activities.
lacp port-priority
Sets the priority of a port.
show lacp
Displays information about LACP activity on the
device.
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lbo
lbo
To set a cable length longer than 655 feet for a DS-1 link, use thelbocommand in interface configuration mode
on the interface for a T1 link. To delete the lbovalue, use the no form of this command.
lbo {long {gain26| gain36} {-15db| -22.5db| -7.5db| 0db}| short {133| 266| 399| 533| 655}}
no lbo
Syntax Description
long
Specifies the long-haul mode where the gain and line
build out must be configured.
gain26
Specifies the decibel pulse gain at 26 decibels. This
is the default pulse gain.
gain36
Specifies the decibel pulse gain at 36 decibels.
-15db
Specifies the decibel pulse rate at -15 decibels.
-22.5db
Specifies the decibel pulse rate at -22.5 decibels.
-7.5db
Specifies the decibel pulse rate at -7.5 decibels.
0db
Specifies the decibel pulse rate at 0 decibels. This is
the default.
short
Specifies the short-haul mode where the cable length,
in feet, must be configured.
133
Specifies a cable length from 0 to 133 feet.
266
Specifies a cable length from 134 to 266 feet.
399
Specifies a cable length from 267 to 399 feet.
533
Specifies a cable length from 400 to 533 feet.
655
Specifies a cable length from 534 to 655 feet.
Command Default
gain26 and0db
Command Modes
Interface configuration
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lbo
Command History
Usage Guidelines
Release
Modification
11.3MA
This command was introduced as a Cisco MC3810 controller configuration
command.
12.0(5)XE
The command was introduced as an ATM interface command.
12.0(7)XE1
This command was implemented on Cisco 7100 series routers.
12.1(5)T
This command was integrated into Cisco IOS Release 12.1(5)T.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support
in a specific 12.2SX release of this train depends on your feature set, platform,
and platform hardware.
This command is supported on T1 links only.
Each T1 port can operate in long-haul or short-haul mode. In long haul mode, the user must specify the gain
and the line build out. In short-haul mode, the user must specify the cable length in feet.
The transmit attenuation value is best obtained by experimentation. If the signal received by the far-end
equipment is too strong, reduce the transmit level by entering additional attenuation.
Examples
On Cisco 7100 or Cisco 7200 series routers, the following example specifies a pulse gain of 36 decibels and
a decibel pulse rate of -7.5 decibels:
Router(config)# interface atm 1/2
Router(config-if)# lbo long gain36 -7.5db
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lex burned-in-address
lex burned-in-address
To set the burned-in MAC address for a LAN Extender interface, use the lexburned-in-address command
in interface configuration mode. To clear the burned-in MAC address, use the no form of this command.
lex burned-in-address ieee-address
no lex burned-in-addresslex burned-in-address command
Syntax Description
ieee-address
48-bit IEEE MAC address written as a dotted triplet
of 4-digit hexadecimal numbers.
Command Default
No burned-in MAC address is set.
Command Modes
Interface configuration
Command History
Release
Modification
10.3
This command was introduced.
12.2(15)T
This command is no longer supported in Cisco_IOS Mainline or
Technology-based (T) releases. It may continue to appear in Cisco_IOS
12.2S-family releases.
Usage Guidelines
Use this command only on a LAN Extender interface that is not currently active (not bound to a serial interface).
Examples
The following example sets the burned-in MAC address on LAN Extender interface 0:
Router(config)# interface serial 4
Router(config-if)# encapsulation ppp
Router(config)# interface lex 0
Router(config-if)# lex burned-in-address 0000.0c00.0001
Router(config-if) ip address 10.108.172.21 255.255.255.0
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lex input-address-list
lex input-address-list
To assign an access list that filters on MAC addresses, use the lexinput-address-list command in interface
configuration mode. To remove an access list from the interface, use the no form of this command.
lex input-address-list access-list-number
no lex input-address-listlex input-address-list command
Syntax Description
access-list-number
Number of the access list assigned with the access-list
global configuration command. It can be a number
from 700 to 799.
Command Default
No access lists are preassigned to a LAN Extender interface.
Command Modes
Interface configuration
Command History
Usage Guidelines
Release
Modification
10.0
This command was introduced.
12.2(15)T
This command is no longer supported in Cisco_IOS Mainline or
Technology-based (T) releases. It may continue to appear in Cisco_IOS
12.2S-family releases.
Use the lexinput-address-list command to filter the packets that are allowed to pass from the LAN Extender
to the core router. The access list filters packets on the basis of the source MAC address.
The LAN Extender interface does not process MAC-address masks. Therefore, you should omit the mask
from the access-list commands.
For LAN Extender interfaces, an implicit permit everything entry is automatically defined at the end of an
access list. Note that this default differs from other access lists, which have an implicit deny everything entry
at the end of each access list.
Examples
The following example applies access list 710 to LAN Extender interface 0. This access list denies all packets
from MAC address 0800.0214.2776 and permits all other packets.
Router(config-if)# access-list 710 deny 0800.0214.2776
Router(config)# interface lex 0
Router(config-if)# lex input-address-list 710
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lex input-address-list
Related Commands
Command
Description
access-list
Configures the access list mechanism for filtering
frames by protocol type or vendor code.
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lex input-type-list
lex input-type-list
To assign an access list that filters Ethernet packets by type code, use the lexinput-type-list command in
interface configuration mode. To remove an access list from an interface, use the no form of this command.
lex input-type-list access-list-number
no lex input-type-list lex input-type-list command
Syntax Description
access-list-number
Number of the access list that you assigned with the
access-list command. It can be a number in the range
200 to 299.
Command Default
No access lists are preassigned to a LAN Extender interface.
Command Modes
Interface configuration
Command History
Usage Guidelines
Release
Modification
10.3
This command was introduced.
12.2(15)T
This command is no longer supported in Cisco_IOS Mainline or
Technology-based (T) releases. It may continue to appear in Cisco_IOS
12.2S-family releases.
Filtering is done on the LAN Extender chassis.
The LAN Extender interface does not process masks. Therefore, you should omit the mask from the access-list
commands.
For LAN Extender interfaces, an implicit permit everything entry is automatically defined at the end of an
access list. Note that this default differs from other access lists, which have an implicit deny everything entry
at the end of each access list.
Examples
The following example applies access list 220 to LAN Extender interface 0. This access list denies all AppleTalk
packets (packets with a type field of 0x809B) and permits all other packets.
Router(config-if)# access-list 220 deny 0x809B 0x0000
Router(config)# interface lex 0
Router(config-if)# lex input-type-list 220
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lex input-type-list
Related Commands
Command
Description
access-list
Configures the access list mechanism for filtering
frames by protocol type or vendor code.
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lex priority-group
lex priority-group
To activate priority output queueing on the LAN Extender, use the lexpriority-group command in interface
configuration mode. To disable priority output queueing, use the no form of this command.
lex priority-group group
no lex priority-group
Syntax Description
group
Command Default
Disabled
Command Modes
Interface configuration
Command History
Usage Guidelines
Number of the priority group. It can be a number in
the range 1 to 10.
Release
Modification
10.3
This command was introduced.
12.2(15)T
This command is no longer supported in Cisco_IOS Mainline or
Technology-based (T) releases. It may continue to appear in Cisco_IOS
12.2S-family releases.
To define queueing priorities, use the priority-listprotocol global configuration command. Note that you can
use only the following forms of this command:
priority-list
list
protocol
protocol
{
high
|
medium
|
normal
|
low
priority-list
list
protocol
bridge
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lex priority-group
{
high
|
medium
|
normal
|
low
}
list
list-number
If you specify a protocol that does not have an assigned Ethernet type code, such as x25, stun, or pad, it is
ignored and will not participate in priority output queueing.
Examples
The following example activates priority output queueing on LAN Extender interface 0:
Router(config-if)# priority-list 5 protocol bridge medium list 701
Router(config-if)# lex interface 0
Router(config-if)# lex priority-group 5
Related Commands
Command
Description
priority-list protocol
Establishes queueing priorities based on the protocol
type.
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lex retry-count
lex retry-count
To define the number of times to resend commands to the LAN Extender chassis, use the lexretry-count
command in interface configuration mode. To return to the default value, use the no form of this command.
lex retry-count number
no lex retry-count number lex retry-count command
Syntax Description
number
Command Default
10 retries
Command Modes
Interface configuration
Command History
Number of times to retry sending commands to the
LAN Extender. It can be a number in the range 0 to
100. The default is 10.
Release
Modification
10.3
This command was introduced.
12.2(15)T
This command is no longer supported in Cisco_IOS Mainline or
Technology-based (T) releases. It may continue to appear in Cisco_IOS
12.2S-family releases.
Usage Guidelines
After the router has sent a command the specified number of times without receiving an acknowledgment
from the LAN Extender, it stops sending the command altogether.
Examples
The following example resends commands 20 times to the LAN Extender:
Router(config-if)# lex interface 0
Router(config-if)# lex retry-count 20
Related Commands
Command
Description
lex timeout
Defines the amount of time to wait for a response
from the LAN Extender.
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lex timeout
lex timeout
To define the amount of time to wait for a response from the LAN Extender, use the lextimeout command
in interface configuration mode. To return to the default time, use the no form of this command.
lex timeout milliseconds
no lex timeout [ milliseconds ] lex timeout command
Syntax Description
milliseconds
Command Default
2000 ms (2 seconds)
Command Modes
Interface configuration
Command History
Time, in milliseconds, to wait for a response from the
LAN Extender before resending the command. It can
be a number in the range 500 to 60,000. The default
is 2000 ms.
Release
Modification
10.3
This command was introduced.
12.2(15)T
This command is no longer supported in Cisco_IOS Mainline or
Technology-based (T) releases. It may continue to appear in Cisco_IOS
12.2S-family releases.
Usage Guidelines
The lextimeout command defines the amount of time that the router waits to receive an acknowledgment
after having sent a command to the LAN Extender.
Examples
The following example causes unacknowledged packets to be resent at 4-second intervals:
Router(config-if)# lex interface 0
Router(config-if)# lex timeout 4000
Related Commands
Command
Description
lex retry-count
Defines the number of times to resend commands to
the LAN Extender chassis.
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linecard-group y-cable
linecard-group y-cable
To create a line card group for one-to-one line card redundancy, use the linecard-group y-cable command in
redundancy mode. To remove the line card redundancy group, use the no form of this command.
linecard-group linecard-groupId y-cable
no linecard-group linecard-groupId y-cable
Syntax Description
linecard-groupId
An unsigned integer in the range 0 to the (maximum
number of chassis line card subslots/2) -1.
y-cable
The link protection type for the line card group.
Command Default
No default behavior or values .
Command Modes
Redundancy
Command History
Release
Modification
12.2(28)SB
This command was introduced on the Cisco 10000 series router.
Usage Guidelines
The no linecard-group y-cable command removes the line card redundancy group and frees the
linecard-groupIdfor reuse. The no linecard-group y-cable command succeeds only if there are no subslot
members in the line card redundancy group.
Examples
The following example creates line card group number 1 for one-to-one line card redundancy:
Router(config)# redundancy
Router(config-red)# linecard-group 1 y-cable
Related Commands
Command
Description
member subslot
Configures the redundancy role of a line card in the
line card group.
redundancy
Enters redundancy mode.
show redundancy linecard
Displays information about a redundant line card or
line card group.
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linecard-group y-cable
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linecode
linecode
To select the line-code type for T1 or E1 lines, use the linecode command in controller configuration mode.
linecode {ami| b8zs| hdb3}
Syntax Description
ami
Specifies alternate mark inversion (AMI) as the
line-code type. Valid for T1 or E1 controllers. This
is the default for T1 lines.
b8zs
Specifies B8ZS as the line-code type. Valid for T1
controller only.
hdb3
Specifies high-density bipolar 3 (hdb3) as the
line-code type. Valid for E1 controller only. This is
the default for E1 lines.
Command Default
AMI is the default for T1 lines. High-density bipolar 3 is the default for E1 lines.
Command Modes
Controller configuration
Command History
Usage Guidelines
Release
Modification
10.3
This command was introduced.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support
in a specific 12.2SX release of this train depends on your feature set, platform,
and platform hardware.
Use this command in configurations in which the router or access server must communicate with T1 fractional
data lines. The T1 service provider determines which line-code type, either ami or b8zs, is required for your
T1 circuit. Likewise, the E1 service provider determines which line-code type, either ami or hdb3, is required
for your E1 circuit.
This command does not have a no form.
Examples
The following example specifies B8ZS as the line-code type:
Router(config-controller)# linecode b8zs
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line-mode
line-mode
To configure the mode of the controller for the Symmetrical High-Speed Digital Subscriber Line (SHDSL)
port, use the line-mode command in controller configuration mode. To return to the default two-wire mode,
use the no form of this command.
line-mode [2-wire| 4-wire [enhanced| standard]| auto]
no line-mode
Syntax Description
2-wire
(Optional) Configures the controller to operate in
two-wire mode.
4-wire
(Optional) Configures the controller to operate in
four-wire mode.
enhanced
(Optional) Configures 4-wire mode to exchange
handshake status on both wire pairs. This is the
default if the handshake mode is not specified.
standard
(Optional) Configures 4-wire mode to exchange
handshake status on the master wire pair only.
auto
(Optional) Configures the controller to automatically
operate in the mode to match the other line
termination. This mode is compatible with a remote
host that is in one of the following modes:
• line-mode 2-wire line 0
• line-mode 2-wire line 1
• line-mode 4-wire enhanced
Command Default
The default is two-wire mode if this command is omitted or if the 4-wire keyword is omitted.
Command Modes
Controller configuration
Command History
Release
Modification
12.3(4)XD
This command was introduced on Cisco 2600 series and Cisco 3700 series
routers.
12.3(7)T
This command was integrated into Cisco IOS Release 12.3(7)T on Cisco
2600 series and Cisco 3700 series routers.
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line-mode
Usage Guidelines
Release
Modification
12.3(11)T
This command was implemented on Cisco 2800 and Cisco 3800 series
routers.
12.3(14)T
This command was implemented on Cisco 1800 series routers.
12.4(2)XA
The enhanced and standard keywords were added to four-wire mode.
12.4(5)A
Modified auto keyword to to disallow use of line-rate command
12.4(4)T
Modified auto keyword to to disallow use of line-rate command
This command is used to configure the controller for two-wire or four-wire mode.
Note
To operate in four-wire mode for SHDSL, the line-mode4-wirecommand must be set.
Note
When the line-mode command is set to auto, the line-rate command is not available.
Examples
Examples
The following example shows how to configure the controller mode of DSL on the controller in slot 4 and
port 0 to operate in four-wire mode:
Router(config)# controller dsl 4/0
Router(config-controller)# line-mode
4-wire
Examples
The following example configures the controller in slot 1 and port 0. The router is set to terminate as CPE
with the line mode automatically selecting between two-wire mode and four-wire mode.
Router(config)# controller dsl 1/0
Router(config-controller)# line-mode auto
Router(config-controller)# line-term cpe
Related Commands
Command
Description
line-rate
Specifies a line rate for the DSL controller.
line-term
Specifies a termination for a line.
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line-rate
line-rate
To specify a line rate for the DSL controller, use the line-rate command in controller configuration mode.
line-rate {auto| rate}
Syntax Description
auto
Allows the controller to select the rate. This option
is available only in two-wire mode.
rate
DSL line rate, in kbps. The line will train at the
selected rate plus 8 kbps of DSL framing overhead.
The supported line rates are as follows:
• For two-wire mode:
• 192, 256, 320, 384, 448, 512, 576, 640,
704, 768, 832, 896, 960, 1024, 1088, 1152,
1216, 1280, 1344, 1408, 1472, 1536, 1600,
1664, 1728, 1792, 1856, 1920, 1984, 2048,
2112, 2176, 2240, and 2304
• For four-wire mode:
• 384, 512, 640, 768, 896, 1024, 1152, 1280,
1408, 1536, 1664, 1792, 1920, 2048, 2176,
2304, 2432, 2560, 2688, 2816, 2944, 3072,
3200, 3328, 3456, 3584, 3712, 3840, 3968,
4096, 4224, 4352, 4480, and 4608
Command Default
No default behavior or values.
Command Modes
Controller configuration
Command History
Release
Modification
12.3(4)XD
This command was introduced on Cisco 2600 series and Cisco 3700 series
routers.
12.3(4)XG
This command was implemented on Cisco 1700 series routers.
12.3(7)T
This command was integrated into Cisco IOS Release 12.3(7)T on Cisco 2600
series and Cisco 3700 series routers.
12.(11)T
This command was implemented on Cisco 2800 and Cisco 3800 series routers.
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line-rate
Usage Guidelines
Release
Modification
12.3(14)T
This command was implemented on Cisco 1800 series routers.
12.4(5)A
Modified line-rate command to be disallowed when line-modecommand is
set to auto.
12.4(4)T
Modified line-rate command to be disallowed when line-modecommand is
set to auto.
This command does not have a no form.
This command specifies the DSL line rate for the Symmetrical High-Speed Digital Subscriber Line (SHDSL)
port. Use this command to configure the line rate in two-wire or four-wire mode. The SHDSL rate is in kbps,
but the line trains at the selected rate plus two times the 8 kbps of DSL framing overhead.
Examples
Note
Automatic rate mode (auto) is used only in two-wire mode. It is not available in four-wire mode.
Note
If different DSL line rates are configured at opposite ends of the DSL uplink, the actual DSL line rate is
always the lower rate.
Note
The maximum peak cell rate is 8 kbps less than the line rate.
Note
When the line-mode command is set to auto, the line-rate command is not available.
The following example displays the line-mode command selecting four-wire mode, which is different from
the previous line mode of the router as indicated by the router output, and then the line rate is selected. The
rate of 4608 is selected, and the output of the router is shown.
Router(config)# controller dsl 1/0
Router(config-controller)# line-mode
4-wire
Router(config-controller)#
*Jun 15 18:00:48.159: %CONTROLLER-5-UPDOWN: Controller DSL 1/0, changed state
*Jun 15 18:00:50.159: %LINK-3-UPDOWN: Interface ATM1/0, changed state to down
*Jun 15 18:00:51.159: %LINEPROTO-5-UPDOWN: Line protocol on Interface ATM1/0,
Router(config-controller)# line-rate
4608
Router(config-controller)#
*Jun 15 18:01:36.627: %CONTROLLER-5-UPDOWN: Controller DSL 1/0, changed state
*Jun 15 18:01:36.967: %CONTROLLER-5-UPDOWN: Controller DSL 1/0, changed state
Router(config-controller)# exit
tn
cn
tn
tn
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line-rate
Related Commands
Command
Description
line-mode
Configures the mode of the controller.
line-term
Specifies a termination for a line.
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line-term
line-term
To specify a termination for a line, use the line-term command in controller configuration mode.
line-term {co| cpe}
Syntax Description
co
Central office.
cpe
Customer premises equipment. This is the default.
Command Default
The default value is cpe.
Command Modes
Controller configuration
Command History
Usage Guidelines
Release
Modification
12.3(4)XD
This command was introduced on Cisco 2600 series and Cisco 3700 series
routers.
12.3(7)T
This command was integrated into Cisco IOS Release 12.3(7)T on Cisco
2600 series and Cisco 3700 series routers.
12.3(11)T
This command was implemented on Cisco 2800 and Cisco 3800 series routers.
12.3(14)T
This command was implemented on Cisco 1800 series routers.
This command does not have a no form.
This command is used to configure the line termination for use as either the central office (CO) or the customer
premises equipment (CPE).
Examples
The following example shows how to configure the controller in slot 1 and port 0. The router is set to terminate
as CPE with the line mode automatically selecting between two-wire mode and four-wire mode.
Router(config)# controller dsl 1/0
Router(config-controller)# line-term
cpe
Router(config-controller)# line-mode
auto
No change in line mode
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line-term
Related Commands
Command
Description
line-mode
Configures the mode of the controller.
line-rate
Specifies a line rate for the DSL controller.
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line-termination
line-termination
To set the line termination on an E1 controller, use the line-terminationcommand in controller configuration
mode. To return to the default line termination, use the no form of this command.
line-termination {75-ohm| 120-ohm}
no line-termination
Syntax Description
75-ohm
Specifies 75-ohm unbalanced termination.
120-ohm
Specifies 120-ohm balanced termination. This is the
default.
Command Default
120-ohms
Command Modes
Controller configuration
Command History
Release
Modification
11.3(2)AA
This command was introduced.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support
in a specific 12.2SX release of this train depends on your feature set, platform,
and platform hardware.
Usage Guidelines
This command applies only to E1 controllers. To determine the line termination setting for the controller, use
the showcontrollerse1command.
Examples
In the following example, the line termination is set to 75 ohms for the E1 port located in shelf 6, slot 0, port
0:
Router# configure terminal
Router(config)# controller e1 6/0/0
Router(config-controller)# line-termination 75-ohm
Router(config-controller)# end
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line-termination
Related Commands
Command
Description
show controllers e1
Displays information about the E1 links supported
by the NPM (Cisco 4000) or MIP (Cisco 7500 series).
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link debounce
link debounce
To enable the debounce timer on an interface, use the linkdebounce command in interface configuration
mode. To disable the timer, use the no form of this command.
link debounce [time time]
no link debounce
Syntax Description
Command Default
time time
(Optional) Specifies the extended debounce timer; va
lid values are from 100 to 5000 milliseconds.
The table below lists the debounce timer defaults.
Table 1: Port Debounce Timer Delay Time
Port Type
Debounce Timer Disabled
Debounce Timer Enabled
10BASE-FL ports
300 milliseconds
3100 milliseconds
10/100BASE-TX ports
300 milliseconds
3100 milliseconds
100BASE-FX ports
300 milliseconds
3100 milliseconds
10/100/1000BASE-TX ports
300 milliseconds
3100 milliseconds
1000BASE-TX ports
300 milliseconds
3100 milliseconds
Fiber Gigabit ports
10 milliseconds
100 milliseconds
10-Gigabit ports except
WS-X6501-10GEX4 and
WS-X6502-10GE
10 milliseconds
100 milliseconds
WS-X6501-10GEX4 and
1000 milliseconds
WS-X6502-10GE 10-Gigabit ports
Command Modes
Command History
3100 milliseconds
Interface configuration
Release
Modification
12.2(14)SX
Support for this command was introduced on the Supervisor Engine 720.
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link debounce
Release
Modification
12.2(17a)SX
This command was changed to remove support for the following modules:
• WS-X6501-10GEX4
• WS-X6502-10GE
Usage Guidelines
12.2(17d)SXB
Support for this command on the Supervisor Engine 2 was extended to
Release 12.2(17d)SXB.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
The timetime keyword and argument are supported on Gigabit Ethernet and 10-Gigabit Ethernet interfaces
only.
The linkdebounce command is not supported on the following modules in releases prior to Release 2.2(17a)SX:
• WS-X6501-10GEX4
• WS-X6502-10GE
The debounce timer sets the amount of time that the firmware waits before it notifies the software that the
link is down. The debounce timer does not apply to linkup because the linkup is immediately notified by the
firmware.
The default debounce time applies when you enter the linkdebounce command with no arguments. For
example, when you enter the linkdebouncetime100 command, it is equivalent to entering the linkdebounce
command with no arguments and you will see the following link debounce entry in the configuration:
interface GigabitEthernet1/1
no ip address
link debounce
Enter the showinterfacesdebounce command to display the debounce configuration of an interface.
Examples
This example shows how to configure the debounce timer on a Gigabit Ethernet fiber interface:
Router(config-if)# link debounce time 100
Router(config-if)#
Related Commands
Command
Description
show interfaces debounce
Displays the status and configuration for the debounce
timer.
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link state group
link state group
To configure the link state group, use the linkstategroup command in interface configuration mode.
link state group [ number ] {upstream| downstream}
Syntax Description
number
Specifies a link-state group. The acceptable range of
group number is between 1 to 10 and the default value
is 1.
upstream
Configures the interface as an upstream interface in
the group.
downstream
Configures the interface as a downstream interface
in the group.
Command Default
The default linkstategroupnumber is 1.
Command Modes
Interface configuration (config-if)
Command History
Usage Guidelines
Release
Modification
15.1(1)S
This command was introduced.
Link State Ttracking (LST), also known as trunk failover, is a feature that binds the link state of multiple
interfaces. When you configure LST for the first time, add upstream interfaces to the link state group before
adding the downstream interface, otherwise the downstream interfaces would move into error-disable mode.
The maximum number of link state groups configurable is 10. These are the limitations:
• An interface can only be an upstream or downstream interface.
• An interface cannot be part of more than one link state tracking group.
Examples
The following example shows how to configure the link state group number.
Router# configure terminal
Router(config)# link state track 1
Router(config)# interface gigabitethernet3/1
Router(config-if)# link state group 1 upstream
Router(config-if)# interface gigabitethernet3/3
Router(config-if)# link state group 1 upstream
Router(config-if)# interface gigabitethernet3/5
Router(config-if)# link state group 1 downstream
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link state group
Router(config-if)# interface gigabitethernet3/7
Router(config-if)# link state group 1 downstream
Related Commands
Command
Description
link state track
Configures the link-state track number.
show link state group
Displays the link-state group information.
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link state track
link state track
To configure a link state tracking number, use the linkstatetrack command in global configuration mode.
To restore the default linkstatetracknumber, use the no form of this command.
link state track number
no link state track number
Syntax Description
number
Command Default
The default link state track number is 1.
Command Modes
Global configuration (config)
Command History
Specifies the link state tracking number. The
acceptable range is between 1 and 10 and the default
value is 1.
Release
Modification
15.1(1)S
This command was introduced.
Usage Guidelines
Link State Ttracking (LST), also known as trunk failover, is a feature that binds the link state of multiple
interfaces. When you configure LST for the first time, add upstream interfaces to the link state group before
adding the downstream interface, otherwise the downstream interfaces would move into error-disable mode.
Examples
The following example shows how to configure the link state tracking number.
Router# configure terminal
Router(config)# link state track 1
Related Commands
Command
Description
link state group
Configures the link state group and the interface as
either an upstream or downstream interface in the
group.
show link state group
Displays the link state group information.
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li-slot rp rate
li-slot rp rate
To apply the user specified Packets Per Second (PPS) value when an Lawful Intercept (LI) is provisioned in
RP mode, use the li-slot rp rate command in global configuration mode. To disable the user specified value,
use the no form of this command .
li-slot rp rate pps
Syntax Description
pps
Command Default
No default behavior or values.
Command Modes
Global configuration (config)
Command History
Examples
Packets per second (pps). The range is from 10 to
8500 for SUP720, 10 to 6000 for SUP32, and 10 to
12000 for RSP720.
Release
Modification
15.0(1)S5
This command was introduced on the Cisco 7600 series routers.
This example shows how to apply PPS value when an LI is provisioned in RP mode:
router# configure terminal
router(config)# li-slot rp rate 5000
Related Commands
Command
Description
show mls rate-limit
Displays information about the configured rate
limiters.
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link-test
link-test
To reenable the link-test function on a port on an Ethernet hub of a Cisco 2505 or Cisco 2507 router, use the
link-test command in hub configuration mode. To disable this function, use the no form of this command.
link-test commandlink-test
no link-test
Syntax Description
This command has no arguments or keywords.
Command Default
Enabled
Command Modes
Hub configuration
Command History
Release
Modification
10.3
This command was introduced.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support
in a specific 12.2SX release of this train depends on your feature set, platform,
and platform hardware.
Usage Guidelines
This command applies to a port on an Ethernet hub only. Disable this feature if a 10Base-T twisted-pair device
at the other end of the hub does not implement the link test function.
Examples
The following example disables the link test function on hub 0, ports 1 through 3:
Router(config)#
hub ethernet 0 1 3
Router(config-hub)#
no link-test
Related Commands
Command
Description
hub
Enables and configures a port on an Ethernet hub of
a Cisco 2505 or Cisco 2507 router.
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load-balancing
load-balancing
To apply a load-balancing method to a Gigabit EtherChannel (GEC) interface, use the load-balancing command
in interface configuration mode. To reset to the default, use the no form of this command.
load-balancing {flow| vlan}
no load-balancing
Syntax Description
flow
Flow-based load balancing is used.
vlan
VLAN-manual load balancing is used.
Command Default
The port channel uses the global load-balancing configuration.
Command Modes
Interface configuration (config-if)
Command History
Usage Guidelines
Release
Modification
Cisco IOS XE Release 2.5
This command was introduced.
The load-balancing command sets the load-balancing method on a specific port channel. The load-balancing
method configured with this command takes precedence over the global configuration defined with the
port-channelload-balancingvlan-manual command.
If you do not explicitly configure load balancing either globally or on the port channel, the load-balancing
method on the port channel is set to flow-based.
Load balancing uses the concept of buckets to map traffic flows to the member links of the port channel. The
different traffic flows are mapped to the buckets and each bucket has one active member link associated with
it. All flows that are mapped to a bucket use the member link associated with that bucket.
There are two methods of load balancing on a GEC interface:
• VLAN-manual--All packets forwarded over the same VLAN subinterface are considered part of the
same flow and are mapped to the member link specified in the configuration.
• Flow-based--Traffic flows are mapped to different member links based on the packet header.
Examples
This example shows how to set the load-balancing method to VLAN-manual:
Router(config)# interface port-channel 1
Router(config-if)# load-balancing vlan
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load-balancing
Related Commands
Command
Description
interface port-channel
Creates a port-channel virtual interface.
port-channel load-balancing vlan-manual
Applies the VLAN-manual load-balancing method
globally to all GEC interfaces.
show interfaces port-channel etherchannel
Displays the load-balancing bucket distribution
currently in use for a GEC interface.
show etherchannel load-balancing
Displays the load-balancing method applied to GEC
interfaces.
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load-interval
load-interval
To change the length of time for which data is used to compute load statistics, use the load-interval command
in interface configuration mode or Frame Relay DLCI configuration mode. To revert to the default setting,
use the noform of this command.
load-interval seconds
no load-interval seconds
Syntax Description
seconds
Length of time for which data is used to compute load
statistics. Value is a multiple of 30, from 30 to 600
(30, 60, 90, 120, and so on). The default is 300
seconds.
Command Default
Enabled
Command Modes
Interface configuration Frame Relay DLCI configuration
Command History
Usage Guidelines
Release
Modification
10.3
This command was introduced.
12.2(4)T
This command was made available in Frame Relay DLCI configuration
mode.
12.2(18)SXF
Support for this command was introduced on the Supervisor Engine 720.
12.2(28)SB
This command was integrated into Cisco IOS Release 12.2(28)SB.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
15.1(2)SNG
This command was implemented on the Cisco ASR 901 Series Aggregation
Services Routers.
To make computations more reactive to short bursts of traffic, you can shorten the length of time over which
load averages are computed.
If the load interval is set to 30 seconds, new data is used for load calculations over a 30-second period. This
data is used to compute load statistics, including the input rate in bits and packets per second, the output rate
in bits and packets per second, the load, and reliability.
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load-interval
Load data is gathered every five seconds. This data is used for a weighted-average calculation in which recent
load data has more weight in the computation than older load data. If the load interval is set to 30 seconds,
the average is computed for the last 30 seconds of load data.
If you change the calculation interval from the default of five minutes to a shorter period of time, the input
and output statistics that are displayed by the show interface command or the show frame-relay pvc command
will be more current and will be based on more nearly instantaneous data, rather than reflecting the average
load over a longer period of time.
This command is often used for dial backup purposes to increase or decrease the likelihood of implementation
of a backup interface, but it can be used on any interface.
Examples
Examples
In the following example, the default average of five minutes is changed to a 30-second average. A burst in
traffic that would not trigger a dial backup for an interface configured with the default five-minute interval
might trigger a dial backup for this interface, which is set for the shorter 30-second interval.
Router(config)# interface serial 0
Router(config-if)# load-interval 30
Examples
In the following example, the load interval is set to 60 seconds for a Frame Relay PVC with the DLCI 100:
Router(config)# interface serial 1/1
Router(config-if)# frame-relay interface-dlci 100
Router(config-fr-dlci)# load-interval 60
Related Commands
Command
Description
show interfaces
Displays statistics for all interfaces configured on the
router or access server.
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local ip address
local ip address
To define an IP address to identify a local circuit emulation (CEM) channel, use the localipaddresscommand
in CEM xconnect configuration mode.
local ip address ip-address
Syntax Description
ip-address
IP address of a regular or loopback interface in the
local router. Default is 0.0.0.0
Command Default
The default local IP address is 0.0.0.0 for a CEM channel.
Command Modes
CEM xconnect configuration
Command History
Usage Guidelines
Release
Modification
12.3(7)T
This command was introduced.
This command does not have a no form. To remove a local IP address, either configure a new local IP address
or enter the noxconnect command to disable the connection and all its parameters.
The local IP address used to identify the local end of a CEM connection must be the same as the IP address
defined by the remote-ip-addressargument used in the xconnect command to identify the CEM channel at
the other end of the CEM connection.
Note
Examples
If there are multiple CEM connections that originate from the same router, they may share the same local
IP address provided that each local IP address defines a unique UDP port number using thelocaludpport
command.
The following example demonstrates how to configure the IP address of the local endpoint of the CEM over
IP (CEoIP) connection.
Router(config-cem-xconnect)# local ip address 10.0.5.1
Related Commands
Command
Description
clear cem
Clears CEM statistics.
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local ip address
Command
Description
local udp port
Defines the UDP port at the local end of a CEM
connection.
show cem
Displays CEM statistics.
xconnect (CEM)
Builds one end of a CEM connection and enters CEM
xconnect configuration mode.
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local udp port
local udp port
To define the User Datagram Protocol (UDP) port of the local endpoint of a circuit emulation (CEM) connection,
use the localudpportcommand in CEM xconnect configuration mode.
local udp port port
Syntax Description
port
Number of the CEM local UDP port. Possible values
are 0, 2141, and 15872 through 16383. The default
is 0.
Command Default
The default local UDP port number is 0 for the local endpoint of a CEM connection.
Command Modes
CEM xconnect configuration
Command History
Release
Modification
12.3(7)T
This command was introduced.
Usage Guidelines
This command does not have a no form. To remove a local UPD port number, either configure a new UPD
port number or enter the noxconnect command to disable the connection and all its parameters.
Examples
The following example demonstrates how to configure the UDP port of the local endpoint of the CEM over
IP (CEoIP) connection.
Router(config-cem-xconnect)# local udp port 2141
Related Commands
Command
Description
remote udp port
Defines the UDP port of the remote endpoint of a
CEM connection.
show cem
Displays CEM channel statistics.
xconnect (CEM)
Builds one end of a CEM connection and enters CEM
xconnect configuration mode.
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local-lnm
local-lnm
To enable Lanoptics Hub Networking Management of a PCbus Token Ring interface, use the local-lnm
command in interface configuration mode. To disable Lanoptics Hub Networking Management, use the no
form of this command.
local-lnm commandlocal-lnm
no local-lnm
Syntax Description
This command has no arguments or keywords.
Command Default
Management is not enabled.
Command Modes
Interface configuration
Command History
Release
Modification
10.3
This command was introduced.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support
in a specific 12.2SX release of this train depends on your feature set, platform,
and platform hardware.
Usage Guidelines
The Token Ring interface on the AccessPro PC card can be managed by a remote LAN manager over the
PCbus interface. At present, the Lanoptics Hub Networking Management software running on an IBM
compatible PC is supported.
Examples
The following example enables Lanoptics Hub Networking Management:
Router(config-if)# local-lnm
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logging event
logging event
To enable notification of interface, subinterface, and Frame Relay data link connection identifier (DLCI) data
link status changes, use the loggingevent command in interface configuration mode. To disable notification,
use the no form of this command.
logging event {dlci-status-change| link-status| subif-link-status [ignore-bulk]}
no logging event {dlci-status-change| link-status| subif-link-status [ignore-bulk]}
Syntax Description
Enables notification of Frame Relay DLCI status
changes.
dlci-status-change
Note
Command Default
This option is supported only when the
encapsulation on the interface is Frame
Relay.
link-status
Enables notification of interface data link status
changes.
subif-link-status
Enables notification of subinterface data link status
changes.
ignore-bulk
Suppresses link status messages for subinterfaces
when they are caused by a state change of the main
interface.
For system images, notification of interface, subinterface, and Frame Relay DLCI data link status changes is
enabled by default.
For boot images, notification of Frame Relay subinterface and DLCI data link status changes is disabled by
default. Notification of interface data link status changes is enabled by default.
Command Modes
Command History
Interface configuration
Release
Modification
12.0
This command was introduced.
12.2(32)S
The ignore-bulk keyword was integrated into the Cisco IOS Release 12.2(32)S.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.3(7)T
The ignore-bulk keyword was integrated into Cisco IOS Release 12.3(7)T.
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logging event
Examples
Release
Modification
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support
in a specific 12.2SX release of this train depends on your feature set, platform,
and platform hardware.
The following example shows how to enable notification of subinterface link status changes:
Router(config-if)# logging event subif-link-status
The following are examples of Frame Relay DLCI and subinterface status change notification messages
filtered by the loggingevent command:
00:16:22: %FR-5-DLCICHANGE: Inteface Serial3/0/0:1 - DLCI 105 state changed to INACTIVE
00:16:22: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial3/0/0:1.5, changed state
to down
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logging source-interface
logging source-interface
To specify the source IPv4 or IPv6 address of system logging packets, use the loggingsource-interface
command in global configuration mode . To remove the source designation, use the no form of this command.
logging source-interface type number
no logging source-interface
Syntax Description
type number
Interface type and number.
Command Default
The wildcard interface address is used.
Command Modes
Global configuration (config)
Command History
Usage Guidelines
Release
Modification
11.2
This command was introduced.
12.4(4)T
This command was modified. IPv6 support was added.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX. Support in a
specific 12.2SX release of this train depends on your feature set, platform,
and platform hardware.
This command can be configured on the Virtual Routing and Forwarding (VRF) and non-VRF interfaces.
Normally, a syslog message contains the IPv4 or IPv6 address of the interface used to leave the router. The
loggingsource-interface command configures the syslog packets contain the IP or IPv6 address of a particular
interface, regardless of which interface the packet uses to exit the router.
When no specific interface is configured, a wildcard interface address of 0.0.0.0 (for IPv4) or :: (for IPv6) is
used, and the IP socket selects the best outbound interface.
Examples
In the following example, the user specifies that the IP address of Ethernet interface 0 is the source IP address
for all syslog messages:
Router(config)# logging source-interface ethernet 0
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logging source-interface
The following example specifies that the IP address for Ethernet interface 2/1 is the source IP address for all
syslog messages:
Router(config)# logging source-interface ethernet 2/1
The following sample output displays that the loggingsource-interface command is configured on a VRF
source interface:
Router# show running interface loopback49
Building configuration...
Current configuration : 84 bytes
!
interface Loopback49
ip vrf forwarding black
ip address 49.0.0.1 255.0.0.0
end
Router# show running | includes logging
logging source-interface Loopback49 vrf black
logging host 130.0.0.1 vrf black
Related Commands
Command
Description
logging
Logs messages to a syslog server host.
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logging event link-status (global configuration)
logging event link-status (global configuration)
To change the default or set the link-status event messaging during system initialization, use the logging event
link-status command in global configuration mode. To disable the link-status event messaging, use the no
form of this command.
logging event link-status {default| boot}
no logging event link-status {default| boot}
Syntax Description
default
Enables system logging of interface state-change
events on all interfaces in the system.
boot
Enables system logging of interface state-change
events on all interfaces in the system during system
initialization.
Command Default
Interface state-change messages are not sent.
Command Modes
Global configuration
Command History
Usage Guidelines
Release
Modification
12.2(14)SX
Support for this command was introduced on the Supervisor Engine 720.
12.2(17d)SXB
Support for this command on the Supervisor Engine 2 was extended to
Release 12.2(17d)SXB.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
You do not have to enter the logging event link-status boot command to enable link-status messaging during
system initialization. The logging event link-status default command logs system messages even during
system initialization.
If you enter both the logging event link-status default and the no logging event link-status bootcommands,
the interface state-change events are logged after all modules in the Cisco 7600 series router come online after
system initialization. The logging event link-status default and the no logging event link-status boot
commands are saved and retained in the running configuration of the system.
When both the logging event link-status default and the no logging event link-status bootcommands are
present in the running configuration and you want to display the interface state-change messages during system
initialization, enter the logging event link-status boot command.
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logging event link-status (global configuration)
Examples
This example shows how to enable the system logging of the interface state-change events on all interfaces
in the system:
Router(config)# logging event link-status default
Router(config)#
This example shows how to enable the system logging of interface state-change events on all interfaces during
system initialization:
Router(config)# logging event link-status boot
Router(config)#
This example shows how to disable the system logging of interface state-change events on all interfaces:
Router(config)# no logging event link-status default
Router(config)#
This example shows how to disable the system logging of interface state-change events during system
initialization:
Router(config)# no logging event link-status boot
Router(config)#
Related Commands
Command
Description
show running-config
Displays the status and configuration of the module
or Layer 2 VLAN.
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logging event link-status (interface configuration)
logging event link-status (interface configuration)
To enable link-status event messaging on an interface, use the logging event link-status command in interface
configuration mode. To disable link-status event messaging, use the no form of this command.
logging event link-status [bchan| dchan| nfas]
no logging event link-status [bchan| dchan| nfas]
Syntax Description
bchan
(Optional) Logs B-channel status messages. This
keyword is available only for integrated services
digital network (ISDN) serial interfaces.
dchan
(Optional) Logs D-channel status messages. This
keyword is available only for ISDN serial interfaces.
nfas
(Optional) Logs non-facility associated signaling
(NFAS) D-channel status messages. This keyword is
available only for ISDN serial interfaces.
Command Default
Interface state-change messages are not sent.
Command Modes
Interface configuration (config-if)
Command History
Release
Modification
12.2(14)SX
This command was introduced on the Supervisor Engine 720.
12.2(17d)SXB
This command was modified to support the Supervisor Engine 2.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
Usage Guidelines
To enable system logging of interface state-change events on a specific interface, enter the logging event
link-status command.
Examples
The following example shows how to enable link-status event messaging on an interface:
Router(config-if)# logging event link-status
This example shows how to disable link-status event messaging on an interface:
Router(config-if)# no logging event link-status
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logging event subif-link-status
logging event subif-link-status
To enable the link-status event messaging on a subinterface, use the logging event subif-link-status command
in interface configuration mode. To disable the link-status event messaging on a subinterface, use the no form
of this command.
logging event subif-link-status
no logging event subif-link-status
Syntax Description
This command has no arguments or keywords.
Command Default
Subinterface state-change messages are not sent.
Command Modes
Interface configuration
Command History
Usage Guidelines
Release
Modification
12.2(17d)SXB
Support for this command on the Supervisor Engine 2 was extended to
Release 12.2(17d)SXB.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
This command is not supported on Cisco 7600 series routers that are configured with a Supervisor Engine
720.
To enable system logging of interface state-change events on a specific subinterface, enter the logging event
subif-link-status command.
To enable system logging of interface state-change events on a specific interface, enter the logging event
link-status command.
To enable system logging of interface state-change events on all interfaces in the system, enter the logging
event link-status command.
Examples
This example shows how to enable the system logging of the interface state-change events on a subinterface:
Router(config-if)# logging event subif-link-status
Router(config-if)#
This example shows how to disable the system logging of the interface state-change events on a subinterface:
Router(config-if)# no logging event subif-link-status
Router(config-if)#
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logging event subif-link-status
Related Commands
Command
Description
show running-config
Displays the status and configuration of the module
or Layer 2 VLAN.
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logging-events
logging-events
to print typical T3 controller Up and Down messages on a Channelized T3 Port Adapter,use the
logging-eventscommandin T3 controller configuration
mode.UsethenoformofthiscommandtodisableprintingoftheT3controllerUpandDownmessages.
logging-events [detail]
[no] logging-events
Syntax Description
(Optional) Enables printing the reason code when a
T3 controller changes from the Up to Down state.
detail
Command Default
The logging-eventscommandisthedefault.
Command Modes
T3 controller configuration
Command History
Release
Modification
12.2(19c)
This command was introduced.
Usage Guidelines
When the no logging-events command disables printing of the T3 controller Up and Down messages,
these messages will neither appear on the console nor in the logs.
Examples
The following example uses the logging-events [detail] command to show the Out-of-Frame (OOF) reason
code when the T3 controller changes from an Up state to a Down state:
Router(config-controller)# logging-events detail
*Jun 19 17:47:50: %CONTROLLER-5-DOWNDETAIL: Controller T3 4/1, changed state to down due
to OOF
Related Commands
Command
Description
t1 logging-events
Prints the typical T1 controller Up and Down
messages on a channelized T3 port adapter.
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logging-events (T1-E1 controller)
logging-events (T1-E1 controller)
To show the controller state change and alarms on a controller, use the logging-eventscommand in controller
configuration mode. To turn off controller state change reporting, use the no form of the command.
logging-events detail
no logging-events
Syntax Description
detail
Command Default
Logging-events is the default.
Command Modes
Controller configuration
Command History
Alarm along with the controller state change.
Release
Modification
12.2(18)SXE
This command was introduced to support SPAs on the Cisco 7600 series
router and Catalyst 6500 series switch.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
Usage Guidelines
Use the logging-eventscommand to show the state change and alarms on a controller on an 8-Port Channelized
T1/E1 Serial SPA.
Examples
The following shows enabling the logging-events command.
Router(config)#contr e1 2/1/0
Router(config-controller)# logging-events
Related Commands
Command
Description
controller
Configures a T1, E1, or T3 controller and enters
controller configuration mode.
show controller
Displays controller configuration.
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loopback (CEM)
loopback (CEM)
To set the loopback method for testing a T1, E1, or serial CEM interface, use the loopback command in
controller configuration or CEM configuration mode. To remove any existing loopback, use the no form of
this command.
Cisco NM-CEM-4SER
loopback {local| network}
no loopback
Cisco NM-CEM-4TE1
loopback {local {payload| line}| network}
no loopback
Syntax Description
Places the interface into local loopback mode and
creates a loopback wherein information received from
the locally-attached customer premises equipment
(CPE) is transmitted back to the locally-attached CPE.
local
• payload --(Used only if a local loopback is
specified for a T1/E1 channel) Creates a
loopback of only the data in individual time
slots. In this mode, framing bits are terminated
and then regenerated instead of being looped
back. This mode is not available if the port is
configured for framingunframed.
• line --(Used only if a local loopback is specified
for a T1/E1 channel) Creates a full physical
layer loopback of all bits, including data and
framing bits.
Creates a loopback wherein data received over the
network from the remote CPE is transmitted back to
the remote CPE.
network
Command Default
No loopback is configured for a CEM interface.
Command Modes
CEM configuration
Command Modes
Controller configuration
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loopback (CEM)
Command History
Usage Guidelines
Release
Modification
12.3(7)T
This command was introduced.
Use this command to create a loopback for a CEM interface. You can use a loopback to test for equipment
malfunction caused by the interface.
The NM-CEM-4TE1 does not respond to loopback requests initiated by the CPE, locally attached or remote,
using the extended super frame (ESF) Facility Data Link (FDL) mechanism or by any other mechanism.
The NM-CEM-4SER does not respond to any form of loopback request initiated by the locally attached or
remote CPE on the Local Loop (LL) or Remote Loop (RL) control leads. Nor does the NM-CEM-4SER
respond to any form of loopback request initiated by the locally attached or remote CPE using in-band loopback
codes.
Examples
The following example shows how to create a loopback on a CEM T1/E1 interface so that data received from
a remote CPE is transmitted back to the remote CPE on the network.
Router(config-controller)# loopback network
The following example shows how to create a loopback of data in individual time slots on a CEM T1/E1
interface. Data received from a locally attached CPE will be sent back to the locally attached CPE.
Router(config-controller)# loopback local payload
The following example shows how to create a loopback on a serial CEM channel so that data received from
a remote CPE is transmitted back to the remote CPE on the network.
Router(config-cem)# loopback network
Related Commands
Command
Description
cem
Enters circuit emulation configuration mode.
controller
Enters controller configuration mode.
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loopback (DSL controller)
loopback (DSL controller)
To test the controller and configure the core loopback, use the loopback(DSLController)command in controller
configuration mode. To remove the loopback interface, use the no form of this command.
loopback {analog| digital}
no loopback
Syntax Description
analog
Loops the circuit at the analog hybrid to verify the
analog loopback hardware to the analog hybrid.
digital
Loops the circuit at the framer to verify the hardware
to the framer.
Command Default
No default behavior or values.
Command Modes
Controller configuration
Command History
Usage Guidelines
Release
Modification
12.3(4)XD
This command was introduced on Cisco 2600 series and Cisco 3700 series
routers.
12.3(4)XG
This command was integrated into Cisco IOS Release 12.3(4)XG on the Cisco
1700 series routers.
12.3(7)T
This command was integrated in Cisco IOS Release 12.3(7)T on Cisco 2600
series, Cisco 3631, and Cisco 3700 series routers.
12.3(11)T
This command was integrated into Cisco IOS Release 12.3(11)T on Cisco 2800
series and Cisco 3800 series routers.
12.3(14)T
This command was integrated into Cisco IOS Release 12.3(14)T on Cisco 1800
series routers.
Analog and digital loopbacks are local loopbacks. Digital loopbacks loop the circuit at the framer to verify
the hardware to the framer, and analog loopbacks loop the circuit at the analog hybrid to verify the analog
loopback hardware to the analog hybrid. The controller must be shut down before loopback can be configured.
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loopback (DSL controller)
Examples
If the controller is still up, the router will prompt you to turn the controller off as shown in this example:
Router(config-controller)# loopback
analog
Please shut down the xDSL controller
Router(config-controller)# loopback
digital
Please shut down the xDSL controller
The following example shows the configuration of a loopback digital interface:
Router(config-controller)# loopback digital
Please shut down the xDSL controller
Router(config-controller)# shutdown
Router(config-controller)#
00:59:50: %CONTROLLER-5-UPDOWN: Controller DSL 0/0, changed state to
administratively down
Router(config-controller)#
Router(config-controller)# loopback digital
Router(config-controller)# no shutdown
Apr 23 06:59:01.435: DSL 0/0 controller Link up! line rate: 4608 Kbps
o
00:59:59: %CONTROLLER-5-UPDOWN: Controller DSL 0/0, changed state to up
Router(config-controller)#end
Router# show controllers dsl 0/0
DSL 0/0 controller UP
Local Digital loopback is running
Globespan xDSL controller chipset
DSL mode: SHDSL Annex B
Frame mode: Utopia
Configured Line rate: 4608Kbps
Line Re-activated 4 times after system bootup
LOSW Defect alarm: ACTIVE
CRC per second alarm: ACTIVE
Line termination: CO
FPGA Revision: 0xA7
Line 0 statistics
Current 15 min CRC: 679
Current 15 min LOSW Defect: 8
Current 15 min ES: 5
Current 15 min SES: 5
Current 15 min UAS: 397
Previous 15 min CRC: 0
Previous 15 min LOSW Defect: 0
Previous 15 min ES: 0
Previous 15 min SES: 0
Previous 15 min UAS: 0
Line 1 statistics
Current 15 min CRC: 577
Current 15 min LOSW Defect: 8
Current 15 min ES: 7
Current 15 min SES: 4
Current 15 min UAS: 411
Previous 15 min CRC: 0
Previous 15 min LOSW Defect: 0
Previous 15 min ES: 0
Previous 15 min SES: 0
Previous 15 min UAS: 0
Line-0 status
Chipset Version: 1
Firmware Version: A29733
Modem Status: un checked mode, Status 83
Last Fail Mode: No Failure status:0x0
Line rate: 2312 Kbps
Framer Sync Status: In Sync
Rcv Clock Status: In the Range
Loop Attenuation: 0.0 dB
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loopback (DSL controller)
Transmit Power: 13.5 dB
Receiver Gain: 936.8420 dB
SNR Sampling: 16.960 dB
Line-1 status
Chipset Version: 1
Firmware Version: A29733
Modem Status: un checked mode, Status 83
Last Fail Mode: No Failure status:0x0
Line rate: 2312 Kbps
Framer Sync Status: In Sync
Rcv Clock Status: In the Range
Loop Attenuation: 0.0 dB
Transmit Power: 13.5 dB
Receiver Gain: 936.8420 dB
SNR Sampling: 16.3590 dB
Dying Gasp: Present
Related Commands
Command
Description
show interfaces loopback
Displays information about the loopback interface.
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loopback (E3 controller)
loopback (E3 controller)
To loop an entire E3 line toward the line and back toward the router, use the loopbackcommand in controller
configuration mode. To remove the loop, use the no form of this command.
loopback {local| network {line| payload}}
no loopback
Syntax Description
Loops the data back toward the router and sends an
AIS signal out toward the network. This is the default.
local
network line
Command Default
local
Command Modes
Controller configuration
Command History
Sets the loopback toward the network either before
going through the framer (line) or after going through
the framer (payload).
payload
Release
Modification
11.3
This command was introduced.
12.2(11)YT
This command was integrated into Cisco IOS Release 12.2(11)YT and
implemented on the following platforms for E3: Cisco 2650XM, Cisco 2651XM,
Cisco 2691, Cisco 3660 series, Cisco 3725, and Cisco 3745 routers.
12.2(15)T
This command was integrated into Cisco IOS Release 12.2(15)T.
Usage Guidelines
Use this command for troubleshooting purposes. To verify that a loopback is configured on the interface, use
the showcontrollerse3EXEC command. Note that line loopback is available only in C-bit parity mode.
Examples
The following example shows how to configure the controller located in slot 1, port 0 for a local loopback:
Router(config)# controller e3 1/0
Router(config-controller)# loopback local
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loopback (E3 controller)
Related Commands
Command
Description
show controllers e3
Displays information about the E3 controllers.
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loopback (interface)
loopback (interface)
To diagnose equipment malfunctions between the interface and device, use the loopbackcommand in interface
configuration mode. To disable the test, use the no form of this command.
loopback
no loopback
Syntax Description
This command has no arguments or keywords.
Command Default
Disabled
Command Modes
Interface configuration
Command History
Usage Guidelines
Release
Modification
10.0
This command was introduced.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support
in a specific 12.2SX release of this train depends on your feature set, platform,
and platform hardware.
Loopback on HSSI Cards
On High-Speed Serial Interface (HSSI) cards, the loopback function configures a two-way internal and external
loop on the HSA applique of the specific interface.
Loopback on MCI and SCI Serial Interface Cards
On MCI and SCI serial interface cards, the loopback functions when a CSU/DSU or equivalent device is
attached to the router or access server. Theloopback command loops the packets through the CSU/DSU to
configure a CSU loop, when the device supports this feature.
Loopback on MCI and MEC Ethernet Cards
On the MCI and MEC Ethernet cards, the interface receives back every packet it sends when the loopback
command is enabled. Loopback operation has the additional effect of disconnecting network server functionality
from the network.
Loopback on CSC-FCI FDDI Cards
On the CSC-FCI FDDI card, the interface receives back every packet it sends when the loopback command
is enabled. Loopback operation has the additional effect of disconnecting network server functionality from
the network.
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loopback (interface)
Loopback on Token Ring Interface Cards
On all Token Ring interface cards (except the 4-megabit CSC-R card), the interface receives back every packet
it sends when the loopback command is enabled. Loopback operation has the additional effect of disconnecting
network server functionality from the network.
Active Loopback Interfaces
To show interfaces currently in loopback operation, use the showinterfacesloopback EXEC command.
Note
Examples
Loopback does not work on an X.21 DTE because the X.21 interface definition does not include a loopback
definition.
The following example configures the loopback test on Ethernet interface 4:
Router(config)# interface ethernet 4
Router(config-if)# loopback
Related Commands
Command
Description
down-when-looped
Configures an interface to inform the system it is
down when loopback is detected.
show interfaces loopback
Displays information about the loopback interface.
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loopback (J1 controller )
loopback (J1 controller )
To set the loopback method for testing the J1 interface, use the loopback command in controller configuration
mode. To turn off loopback, use the no form of this command. This command should be used for testing
purposes only.
loopback {local| line| isolation}
no loopback {local| line| isolation}
Syntax Description
local
Places the interface into local loopback mode.
line
Places the interface into external loopback mode at
the line level.
isolation
Places the interface into both local and line loopback
mode.
Command Default
No loopback is configured.
Command Modes
Controller configuration
Command History
Examples
Release
Modification
11.3 MA
This command was implemented on the Cisco MC3810.
12.0(5)T and 12.0(7)XR
The command was implemented on the Cisco 2600 and Cisco 3600 series.
12.0(5)XE
The command was implemented on the Cisco 7200 and Cisco 7500 series.
12.1(1)T
The command was implemented on the Cisco 2600 series.
12.2(8)T
The command was implemented on the Cisco 2600 and Cisco 3600 series.
The following example establishes a loopback of the incoming J1 signal on controller J1 3/0:
Router(config)# controller j1 3/0
Router(config-controller)# loopback line
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loopback (PA-MC-8TE1+ port adapter)
loopback (PA-MC-8TE1+ port adapter)
To enable loopback testing of data for the PA-MC-8TE1+ port adapter, use the loopback command in interface
configuration mode. To disable loopback testing, use the no form of this command.
loopback [internal| line]
no loopback [internal| line]
Syntax Description
internal
(Optional) Loops any data received at the
PA-MC-8TE1+ port adapter’s network interface back
into the PA-MC-8TE1+ port adapter.
line
(Optional) Loops any data received at the
PA-MC-8TE1+ port adapter’s network interface back
into the network.
Command Default
Loopback mode is not enabled.
Command Modes
Interface configuration
Command History
Examples
Release
Modification
12.2(13)T
This command was introduced.
In the following example, a loopback is set for the PA-MC-8TE1+ port adapter in slot 2:
Router(config)# interface 2/0
Router(config-if)# loopback line
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Source Exif Data:
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