[Cluster-devel] Possible problem with cman init script in CVS HEAD (fence related)

[Robert Peterson <rpeterso@redhat.com>]

Fabio Massimo Di Nitto wrote:
> Hi guys,
>
> I found a corner case where calling fence_tools -w leave will/might hang.
> in my setup where i have 2 nodes cluster:
>
> - both nodes are up
> - poweroff the first one -> OK
> - reboot the second one -> OK
> - the second node comes up again:
>
> cman_tools services will show:
> fence            0     default  00040001 JOIN_START_WAIT
>
> since the first node is "dead" there is never a complete switch to state = none.
>
> if you call fence_tools -w leave it will hang there forever.
>
> in my init scripts I just changed the fence_stop() to use the usual wait 10
> seconds or die kind of loop:
>
>          fence_tool -w leave &
>          for sec in $(seq 1 10); do
>                  if pidof fence_tool &> /dev/null; then
>                          if [ "$sec" = 10 ]; then
>                                  kill $(pidof fence_tool) > /dev/null 2>&1
>                          else
>                                  sleep 1
>                          fi
>                  fi
>          done
>
> Regards
> Fabio
>
> PS I spotted this problem when updating the Ubuntu init scripts, but the code
> used in upstream init script seems to suffer the exact same problem. You also
> want to note that i am not checking for fenced to exit, but for the tools to return.
>
>   
Hi Fabio,

You should be able to do the same thing by specifying -t 10 for a 
ten-second timeout
on fence_tool.  For example:

fence_tool -t 10 -w leave

The default timeout value is five minutes, which means the hang 
shouldn't last
forever at any rate.

Regards,

Bob Peterson
Red Hat Cluster Suite