Have a very unusual issue I'm at a loss to explain (though it is reproducible at this point)...
3750 stack (4x48-ports used as top-of-racks) attached to a ring/star layer-2 mesh of other cluster nodes and central core. Running VRF-lite, about 8 VRFs active plus global, connected to ring/star via 802.1Q trunk, one vlan per VRF backbone. VRFs are running EIGRP, there are some redundant L3 links for load-balancing by bandwidth, standard hello/hold-time (5/15 secs). Somewhere in the process of adding a vlan and creating an SVI (w/ip vrf forwarding ...), the 3750 stack "flapped" with respect to several EIGRP neighbors, for several VRFs, the neighbors logging a hold-time exceeded, followed shortly thereafter by a new neighbor established. The 3750 itself logged hold-time exceeded for several neighbors, followed by new neighbor established. The added vlan was not allowed on any trunk, especially not the backbone ring connection. We checked spanning tree, but doesn't appear to be involved (and downtime was shorter than 30 seconds, assuming the 15 second holdtime is what triggered the route flap). Just for "grins" trying to tie the flap to the added vlan, we did a "no vlan xxx" to remove it. Another flap, on multiple VRFs. We add vlans (local to the routed clusters) quite often, and I don't recall this ever happening before, here or any other node. Ring any bells? Things seem to be stable after the flap, so I can live with it, until the next new vlan request at least. Jeff _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
