[c-nsp] Duplicate IP add on CAt6509

[Hyunseog Ryu]

Are you using HSRP?

Hyun

Dave Lim wrote:
> Anyone have faced this log message of duplicate IP address before?
>
> Here is the network topology
>
> C6509CS01 --------------- C6509CS02
> ---------------
>
> This problem occured for 5 min and brought the customer vlan 1 network. Note
> that the
>
> C6509CS01
> Feb 8 08:08:32: %STANDBY-3-DUPADDR: Duplicate address 10.1.1.253 on Vlan1,
> sourced by 0000.0c07.ac09
>
> VLAN 1 MAC address on C6509CS01
> Vlan1 is up, line protocol is up
> Hardware is Cat6k RP Virtual Ethernet, address is 0009.b63e.cffc (bia
> 0009.b63
>
> C6509CS02
> *Feb 9 01:29:49: %STANDBY-3-DUPADDR: Duplicate address 10.1.1.252 on Vlan1,
> sourced by 0009.b63e.bffc
>
> VLAN 1 MAC address on C6509CS02
> Vlan1 is up, line protocol is up
> Hardware is Cat6k RP Virtual Ethernet, address is 0009.b63e.bffc (bia
> 0009.b63e.bffc)
> Internet address is 10.1.1.252/24
>
> I am suspecting this is a spanning tree loop and causes the switch to see a
> duplicate IP address. But logically, there is no loop between the 2 6509
> unless the port-channel connecting the 2 switches fail and in turns there is
> a loop. But in this cases, STP should kick in.
> _______________________________________________
> cisco-nsp mailing list  cisco-nsp at puck.nether.net
> https://puck.nether.net/mailman/listinfo/cisco-nsp
> archive at http://puck.nether.net/pipermail/cisco-nsp/
>
>
>
>