[ClusterLabs] Antw: Re: When the DC crmd is frozen, cluster decisions are delayed infinitely

[Klaus Wenninger]

On 09/08/2016 08:55 AM, Digimer wrote:
> On 08/09/16 03:47 PM, Ulrich Windl wrote:
>>>>> Shermal Fernando <shermalfe at millenniumit.com> schrieb am 08.09.2016 um 06:41 in
>> Nachricht
>> <8CE6E8D87F896546B9C65ED80D30A4336578CB4A at LG-SPMB-MBX02.lseg.stockex.local>:
>>> The whole cluster will fail if the DC (crm daemon) is frozen due to CPU 
>>> starvation or hanging while trying to perform a IO operation.  
>>> Please share some thoughts on this issue.
>> What is "the whole cluster will fail"? If the DC times out, some recovery will take place.
> Yup. The starved node should be declared lost by corosync, the remaining
> nodes reform and if they're still quorate, the hung node should be
> fenced. Recovery occur and life goes on.
Didn't happen in my test (SIGSTOP to crmd).
Might be a configuration mistake though...
Even had sbd with a watchdog active (amongst
other - real - fencing devices).
Thinking if it might make sense so tickle the
crmd-API from sbd-pacemaker-watcher ...
>
> Unless you don't have fencing, then may $deity of mercy. ;)
>