[c-nsp] FWSM failover state flapping

[Patrick Vanderstocken]

Hello list,

I am setting up 2 FWSM modules ver. 2.2(1) in an inter-chassis
failover environment (2 x 6509 ver. 12.2(18)SXD6).

Just 3 interfaces: inside (SVI to MSFC), outside and a failover
interface consisting of a 2x1Gbps trunk providing failover and
stateful link at the same time.

I use interface monitoring on both inside and outside interfaces but a
'show failover' shows that the outside interfaces are flapping between
"Normal" and "Unknown" states. The link at the outside interface is up
and I can see the correct ARP entry, but anyway I think that if one of
the monitoring tests should fail it would switch into a "Failed"
state.
Unit failover is working fine and the inside interface is always
displayed as "Normal".

I'd be glad to hear any ideas you might have.

Patrick