Configuring IPv6 PIM GR
Pre-configuration Tasks
Before configuring IPv6 PIM GR, complete the following tasks:
- Configure an IPv6 unicast routing protocol to ensure normal unicast routing on the network.
- Enable IPv6 PIM-SM.
Context
Only the AR6300 series support IPv6 PIM GR.
Multicast devices may need to perform active/standby switchovers in some scenarios, for example, when the multicast devices need to be upgraded or their control boards fail. After an active/standby switchover, the new active main control board deletes the forwarding entries on interface boards and re-learns the IPv6 PIM routing table and multicast forwarding table. During this process, multicast traffic is interrupted.
After the PIM GR function is configured, the active main control board of the multicast device backs up IPv6 PIM routing entries and Join/Prune information to be sent upstream to the standby main control board. The interface boards maintain forwarding entries. When an active/standby switchover occurs in the system, the multicast device can quickly send Join messages upstream to maintain the Join state of the upstream multicast device. Then, the IPv6 PIM protocol sends Hello messages carrying Generation IDs to all neighbors with IPv6 PIM-SM enabled. When a downstream multicast device finds that the Generation ID of its neighbor changes, it sends a Join/Prune message to the neighbor so that the neighbor can create new routing entries. This mechanism ensures nonstop forwarding of multicast data on the forwarding plane.
On a network using dynamic RP, when a DR receives a Hello message with a Generation ID different from the previous one, the DR sends a unicast Bootstrap message to the multicast device. The multicast device then restores the RP information from the Bootstrap message. If the multicast device cannot learn RP information from the Bootstrap message, it obtains RP information from the Join/Prune messages received from downstream devices and generates new multicast entries.
Procedure
- Run system-view
The system view is displayed.
- Run pim-ipv6
The PIM-IPv6 view is displayed.
- Run graceful-restart
IPv6 PIM GR is enabled.
By default, IPv6 PIM GR is not enabled.
- (Optional) Run graceful-restart period period
The IPv6 PIM GR period is configured.
By default, the IPv6 PIM GR period is 120 seconds.
Verifying the Configuration
After IPv6 PIM GR is configured, you can run the following commands to check entries in the IPv6 PIM routing table.
- display pim ipv6 routing-table [ ipv6-source-address [ mask mask-length ] | ipv6-group-address [ mask mask-length ] | flags flag-value | fsm | incoming-interface { interface-type interface-number | register } | mode { dm | sm | ssm } | outgoing-interface { exclude | include | match } { interface-type interface-number | none | register } ] * [ outgoing-interface-number [ number ] ]
display pim ipv6 routing-table brief [ ipv6-source-address [ mask mask-length ] | ipv6-group-address [ mask mask-length ] | incoming-interface { interface-type interface-number | register } ] *