[ClusterLabs] Cluster node loss detection.

[Digimer]

On 16/10/15 11:40 AM, Vallevand, Mark K wrote:
> Thanks.  I wasn't completely aware of corosync's role in this.  I see new things in the docs every time I read them.
> 
> I looked up the corosync settings at one time and did it again:
> 	token loss 3000ms
> 	retransmits 10
> So 30s.  Redid my simple testing and got detection times of 22s, 26s, and 25s using very crude methods.
> Any warnings about setting these values to something else?
> We require our customers to use an isolated, private network for cluster communications.  All taken care of in our instructions and cluster configuration scripts.  Network traffic will not be a factor.  So, I'm thinking 1000ms and 5 retransmits as an experiment.

That is very high. I think the default is something like 236ms x 4 losses.

You do have fencing, right?

> I was pretty sure that DLM was just being informed by clustering, but I needed to ask.
> 
> Again, thanks.
> 	
> 
> Regards.
> Mark K Vallevand   Mark.Vallevand at Unisys.com <mailto:Mark.Vallevand at Unisys.com> 
> Never try and teach a pig to sing: it's a waste of time, and it annoys the pig.


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Digimer
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