BSR cannot see RP groups (Reopened)

[michaelinoue]

Description

Reopened from #17181: This issue is identical, with the caveat that it no longer happens every time, but occurs inconsistently.

BSR can advertise RP groups, but itself does not have those groups available in show ipv6 pim rp-info, e.g.
for a BSR host 1, we have no BSR RPs,

host1# show ipv6 pim rp-info
 RP address  group/prefix-list  OIF         I am RP  Source  Group-Type
 fd28::      ff08:1234::/32     eth0        no       Static  ASM

for host 2 (the RP) we do have BSR RPs,

host2# show ipv6 pim rp-info
 RP address  group/prefix-list  OIF  I am RP  Source  Group-Type
 fd28::      ff08::/16          lo   yes      BSR     ASM
 fd28::      ff08:1234::/32     lo   yes      Static  ASM
 fd28::      ff08:1235::/32     lo   yes      BSR     ASM

and for another node host 3 (not RP nor BSR) we have BSR RPs.

host3# show ipv6 pim rp-info
 RP address  group/prefix-list  OIF         I am RP  Source  Group-Type
 fd28::      ff08::/16          eth0        no       BSR     ASM
 fd28::      ff08:1234::/32     eth0        no       Static  ASM
 fd28::      ff08:1235::/32     eth0        no       BSR     ASM

Version

frr-10.2

How to reproduce

Add a candidate bsr. e.g.

host1# conf
host1(config)# router pim6
host1(config-pim6)# bsr candidate-bsr

Add a candidate RP, e.g.

host2# conf
host2(config)# router pim6
host2(config-pim6)# bsr candidate-rp ff08:1234::/32

BSR can advertise RP groups, but itself does not have those groups available in show ipv6 pim rp-info, e.g.
for a BSR host 1, we have no BSR RPs,

host1# show ipv6 pim rp-info
 RP address  group/prefix-list  OIF         I am RP  Source  Group-Type
 fd28::      ff08:1234::/32     eth0        no       Static  ASM

for the RP host 2 (the RP) we do have BSR RPs,

host2# show ipv6 pim rp-info
 RP address  group/prefix-list  OIF  I am RP  Source  Group-Type
 fd28::      ff08::/16          lo   yes      BSR     ASM
 fd28::      ff08:1234::/32     lo   yes      Static  ASM
 fd28::      ff08:1235::/32     lo   yes      BSR     ASM

and for another node host 3 (not RP nor BSR) we have BSR RPs.

host3# show ipv6 pim rp-info
 RP address  group/prefix-list  OIF         I am RP  Source  Group-Type
 fd28::      ff08::/16          eth0        no       BSR     ASM
 fd28::      ff08:1234::/32     eth0        no       Static  ASM
 fd28::      ff08:1235::/32     eth0        no       BSR     ASM

Expected behavior

Expected to see that BSR could see RP groups with show ipv6 pim rp-info

Actual behavior

BSR cannot see RP groups with show ipv6 pim rp-info, e.g.

host1# show ipv6 pim rp-info
 RP address  group/prefix-list  OIF         I am RP  Source  Group-Type
 fd28::      ff08:1234::/32     eth0        no       Static  ASM

Additional context

No response

Checklist

• I have searched the open issues for this bug.
• I have not included sensitive information in this report.

[michaelinoue]

As an update, this issue occurs consistently. After a few minutes, the BSR no longer has the elected RP in its RP table.