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

[emmanuel segura]

*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 at 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 at 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.
>>
>>
>> --
>> Digimer
>> Papers and Projects: https://alteeve.ca/w/
>> What if the cure for cancer is trapped in the mind of a person without
>> access to education?
>>
>
>
>
> --
> esta es mi vida e me la vivo hasta que dios quiera
>



-- 
esta es mi vida e me la vivo hasta que dios quiera
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