Hi all,
I have several routers running OSPF and fully formed PIM neighborship.
AutoRP was configured on one router (172.28.56.51) and also a static RP (10.0.0.6) was configured (it is a reachable IP address)
I did the "show ip mroute" on some first hop routers and observed 2 things:
1. Some routers are listing 224.0.1.40 and 224.0.1.39 as Dense Mode
(*, 224.0.1.40), 7w3d/stopped, RP 0.0.0.0, flags: DCL
(*, 224.0.1.39), 7w3d/stopped, RP 0.0.0.0, flags: DC
A "show ip pim rp mapping" resulted in:
RP 172.28.8.51 (?), v2v1
Info source: 172.28.56.51 (?), elected via Auto-RP
Uptime: 1w4d, expires: 00:02:22
2. Some other routers are listing 224.0.1.40 and 224.0.1.39 as Sparse Mode
(*, 224.0.1.39), 7w0d/00:02:51, RP 10.0.0.6, flags: SJC
(*, 224.0.1.40), 7w0d/00:03:03, RP 10.0.0.6, flags: SJCLF
A "show ip pim rp mapping" resulted in:
Group(s) 224.0.0.0/4
RP 172.28.8.51 (?), v2v1
Info source: 172.28.56.51 (?), elected via Auto-RP
Uptime: 6d06h, expires: 00:02:55
Group(s): 224.0.0.0/4, Static
RP: 10.0.0.6 (?)
First case is totally what I expected as 224.0.1.40 and 224.0.1.39 should operate in Dense Mode by default, and a Auto RP should override a static RP
On all routers, for all other groups, 172.28.56.51 wins over 10.0.0.6 to become RP
Configurations on all 1st hop routers are the same
Can anyone explain to me why that happened?