Additional References For Flex Links And Mac Address-Table Move Update - Cisco Catalyst 2960-XR Configuration Manual

Configuring Flex Links and the MAC Address-Table Move Update Feature
This output shows a querier for VLAN 1 and 401 with their queries reaching the switch through
GigabitEthernet1/0/11:
Switch# show ip igmp snooping querier
Vlan
-------------------------------------------------------------
1
401
This is output for the show ip igmp snooping mrouter command for VLAN 1 and 401:
Switch# show ip igmp snooping mrouter
Vlan
----
1
401
Similarly, both the Flex Links ports are a part of the learned groups. In this example, GigabitEthernet2/0/11
is a receiver/host in VLAN 1, which is interested in two multicast groups:
Switch# show ip igmp snooping groups
Vlan
-----------------------------------------------------------------------
1
1
Whenever a host responds to the general query, the switch forwards this report on all the mrouter ports. When
you turn on this feature through the command-line port, and when a report is forwarded by the switch on
GigabitEthernet1/0/11, it is also leaked to the backup port GigabitEthernet1/0/12. The upstream router learns
the groups and starts forwarding multicast data, which is dropped at the ingress because GigabitEthernet1/0/12
is blocked. When the active link, GigabitEthernet1/0/11, goes down, the backup port, GigabitEthernet1/0/12,
begins forwarding. You do not need to send any proxy reports as the multicast data is already being forwarded
by the upstream router. By leaking reports to the backup port, a redundant multicast path has been set up, and
the time taken for the multicast traffic convergence is very minimal.
Related Topics
Multicast Fast Convergence with Flex Links Failover, on page 150
Additional References for Flex Links and MAC Address-Table
Move Update
Related Documents
Related Topic
Layer 2 command reference
switchport backup interface command
OL-29424-01
IP Address IGMP Version
1.1.1.1 v2
41.41.41.1 v2
ports
-----
Gi1/0/11(dynamic), Gi1/0/12(dynamic)
Gi1/0/11(dynamic), Gi1/0/12(dynamic)
Group Type Version
228.1.5.1 igmp v2
228.1.5.2 igmp v2
Catalyst 2960-XR Switch Layer 2 Configuration Guide, Cisco IOS Release 15.0(2)EX1

Additional References for Flex Links and MAC Address-Table Move Update

Port
Gi1/0/11
Gi1/0/11
Port List
Gi1/0/11, Gi1/0/12, Gi2/0/11
Gi1/0/11, Gi1/0/12, Gi2/0/11
Document Title
Catalyst 2960-XR Switch Layer 2 Command Reference
Catalyst 2960-XR Switch Interface and Hardware Component
Command Reference
165