Brocade Communications Systems IPMC5000PEF manual Multicast non-stop routing

Multicast non-stop routing

To display static multicast groups in the default VRF, enter the following command.

device#show ip igmp static

Group Address Interface Port List

----------------------------------

224.2.2.2v1 ethe 5/2

Syntax: show ip igmp [ vrf vrf_name ] static

The vrf parameter allows you to display static IGMP groups for the VRF instance specified by the vrf_name variable.

Multicast non-stop routing

Multicast non-stop routing (NSR) provides hitless-failover support on all platforms for IPv4 multicast features (default and non-default VRFs): PIM-DM, PIM-SM, and PIM-SSM.

If multicast NSR is enabled, the software state is kept in sync between the active and standby modules. The standby module is NSR ready when the software state of the standby and active modules are in sync. When the standby module is NSR ready, a hitless-failover does not result in a disruption to the multicast forwarding state or traffic

If Multicast NSR is not enabled, or if the standby module is not NSR ready, the software state of the standby and active modules are not in sync. In this case, after a switchover or failover occurs, the new active module enters protocol learning phase for a duration of 55 seconds. During this phase, it learns the protocol state information from its PIM neighbors and local clients. During this period, new multicast flows will not be forwarded, but the existing mutlicast flows (which existed prior to switchover or failover) are forwarded in hardware without any disruption. At the end of the period, all the existing flows are deleted from hardware and they are reprogrammed as per the newly learned state information. Multicast traffic will incur a slight disturbance until the new active module reprograms the hardware with new forwarding state information.

The following message is displayed on the console of the active and standby modules to indicate that the standby module is NSR ready:

Mcastv4 is NSR ready

NOTE

During a hitless-upgrade on FSX platforms, the new active module will always perform the 55 second deferred hardware cleanup even if the NSR is enabled.

Configuration considerations

•Multicast NSR is not supported for IPv6 multicast.

•When multicast NSR is turned on, unicast routing must be protected by NSR or graceful restart on all multicast VRFs.

Configuring multicast non-stop routing

To globally enable multicast non-stop routing for all VRFs, enter the ip multicast-nonstop-routingcommand on the CLI as shown in this example:

Device(config)#ip multicast-nonstop-routing

76	FastIron Ethernet Switch IP Multicast Configuration Guide
	53-1003085-02