Hi Forum,

I have a PIM issue that I am finding hard to pin point. I have multiple 6500 with Sup 720 and IOS 12.2.18SXF8 all running stable except one.

This single 6500 keeps reporting a few times a day a PIM neighbor on ramdom VLAN change it state to DOWN. Please see log entry bellow

Jan 3 04:19:32.940 EST: %PIM-5-NBRCHG: neighbor 1.1.1.2 DOWN on interface Vlan100 (vrf default) DR

Jan 3 04:19:32.940 EST: %PIM-5-DRCHG: DR change from neighbor 1.1.1.2 to 1.1.1.1 on interface Vlan100 (vrf default)

Jan 3 04:19:34.860 EST: %PIM-5-NBRCHG: neighbor 1.1.1.2 UP on interface Vlan100 (vrf default)

Jan 3 04:19:34.860 EST: %PIM-5-DRCHG: DR change from neighbor 1.1.1.1 to 1.1.1.2 on interface Vlan100 (vrf default)

None of all of the other units follow the same behaviour. I looked at drops, discards, load, CPU usage, utilisation, Ethernet Channels, Vlan Interfaces and I can not see anything.

Any ideas are wellcome.

Thanks