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Re: [Linux-cluster] Two-node cluster: Node attempts stateful merge after clean reboot



clean_start: Used to prevent any start up fencing the daemon might
do. It indicates that the daemon should assume all nodes
are in a clean state to start.

So if the cluster network has problem and my cluster is in the spli-brain situation, fencing loop happen, for avoid this situation you have the following choices

1: disable you cluster sotfware to start in the boot time
2: use clean_start=1 with qdisk without expected_votes=1(rgmanager never start the service on node without enaugh vote)
3:change the cluster software :)

Nobody explain me with a technical reason why clean_start=1 is dangerous, so configurare and test well with different parameters your cluster and like that you can understand RHCS


2013/9/12 emmanuel segura <emi2fast gmail com>
Fixed previous mail

clean_start=1 disable the startup fencing and if you use a quorum disk in your cluster without expected_votes=1, when a node start after it has been fenced, the node dosn't try to fence di remain node and doesn't try to start the service, because rgmanager need a cluster quorate, so many people around say clean_start=1 is dangerous, but no one give a clear reason, in my production cluster a i have clvm+vg in exclusive mode+(clean_start=1)+(master_
wins). so if you can explain me where is the problem :) i apriciate



2013/9/11 Digimer <lists alteeve ca>
On 11/09/13 12:04, emmanuel segura wrote:
Hello Pascal

For disable startup fencing you need clean_start=1 in the fence_daemon
tag, i saw in your previous mail you are using expected_votes="1", with
this setting every cluster node will be partitioned into two clusters
and operate independently, i recommended using a quorim disk with
master_wins parameter

This is a very bad idea and is asking for a split-brain, the main reason fencing exists at all.


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Digimer
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