[Linux-cluster] Node is randomly fenced

[yvette hirth]

On 06/12/2014 08:32 AM, Schaefer, Micah wrote:

> Yesterday I added bonds on nodes 3 and 4. Today, node4 was active and
> fenced, then node3 was fenced when node4 came back online. The network
> topology is as follows:
> switch1: node1, node3 (two connections)
> switch2: node2, node4 (two connections)
> switch1 <―> switch2
> All on the same subnet
> 
> I set up monitoring at 100 millisecond of the nics in active-backup mode,
> and saw no messages about link problems before the fence.
> 
> I see multicast between the servers using tcpdump.
> 
> Any more ideas?

spanning-tree scans/rebuilds happen on 10Gb circuits just like they do
on 1Gb circuits, and when they happen, traffic on the switches *can*
come to a grinding halt, depending upon the switch firmware and the type
of spanning-tree scan/rebuild being done.

you may want to check your switch logs to see if any spanning-tree
rebuilds were being done at the time of the fence.

just an idea, and hth
yvette hirth