Specifications

15-45
Cisco MWR 2941 Mobile Wireless Edge Router Release 3.5 Software Configuration Guide, Cisco IOS Release 15.1(3)MR
OL-26895-01
Chapter 15 Configuring Ethernet OAM, CFM, and E-LMI
Enabling Ethernet Loopback
• Port loopback shares hardware resources with the VLAN mapping feature. If not enough TCAM
resources are available because of VLAN-mapping configuration, when you attempt to configure
loopback, you receive an error message, and the configuration is not allowed.
Follow these steps to use Ethernet loopback on the Cisco MWR 2941:
Caution The Cisco MWR 2941 does not support Ethernet loopback while keepalive messages are enabled on the
remote Ethernet interface. Before beginning Ethernet loopback on the Cisco MWR 2941, ensure that you
disable keepalive messages on the remote Ethernet interface. If the remote Ethernet interface is a
Cisco MWR 2941, use the no keepalive command to disable keepalive messages. When you have
completed testing and disabled Ethernet loopback, use the keepalive [period [retries]] command to
enable keepalive messages.
Caution Loopback is supported only in a single direction over an Ethernet link; the Cisco MWR 2941 does not
support bidirectional loopback.
Note Ethernet loopback is only supported on onboard Gigabit Ethernet interfaces it is not supported on HWIC
Ethernet interfaces.
Command Purpose
Step 1
clear mac-address-table [dynamic |
secure] [address mac-address]
[interface type slot/port | vlan vlan-id]
Clear the MAC address table on the router.
Step 1
configure terminal Enter global configuration mode.
Step 2
no mac-address-table learning {vlan
vlan-id | interface interface slot/port}
Disable MAC address learning on the router.
Step 3
interface interface-id Specify the Ethernet interface on which you want to enable Ethernet
loopback.
Step 4
ethernet loopback facility [vlan
vlan-id] swap [timeout {seconds |
none}]
Configure the loopback parameters for the interface.
Step 5
ethernet loopback {start interface-id |
stop {interface-id | all}}
Enable Ethernet loopback on the interface.
Step 6
ethernet loopback {start interface-id |
stop {interface-id | all}}
Disable Ethernet loopback on the interface. You can specify a single
interface or use the all keyword to disable loopback on all Ethernet
interfaces.
Step 7
exit Exit interface configuration mode.
Step 8
mac-address-table learning {vlan
vlan-id | interface interface slot/port}
Enable MAC address learning on the router.
Step 9
show ethernet loopback [interface-id]
[ | {begin | exclude | include}
expression]
Displays the Ethernet loopbacks configured on the router or the specified
interface.