ip pim multipath

Use this command to allow PIM multicast to either load share over ECMP paths or have a single deterministic next hop for ECMP paths.

Syntax

Parameters

Defaults

Multipath will use the first nexthop learned for an ECMP route.

Mode

Configuration command.

Usage

Multipath provides the ability to define the mechanism by which PIM chooses the nexthop. By default, PIM uses the first learned next hop. You can change multipath to use the highest next hop or a next hop based on a hash of the source IP address.

For a deterministic next hop, the highest-nexthop algorithm chooses the numerically highest next hop. The hash algorithm will attempt to spread multicast over all possible next hops.

For the least disruption during network events (including bootup), use the default (first next-hop). The first next hop learned will be the one used regardless of added or removed next hops.

Multipath also allow PIM graceful restart to choose the same next hop after a router failover because the highest-nexthop and the hash algorithms will choose the same next hop, assuming the set of next hops is consistent after the failover.

The “no” form of this command resets the multipath configuration to the default value (using the first next hop).

To view the current multipath setting, use the show running-config pim command.