Consider that the hung/failed node was in the middle of a write to the
SAN and froze. Now imagine at some point in the future it recovers,
having no idea that time passed it has no reason to doubt that it's
locks are still valid so it just finishes the writes. Congrats, you
could have just corrupted your storage.
UMMMMMM2013/9/12 Digimer <lists@xxxxxxxxxx>
The problem that Pascal has is that the node sees the peer, joins and fences anyway. So in this case, clean_start won't help.
Even with a SAN/qdisk though, it's not needed to enable this. If the remaining node can't talk to qdisk, it won't have quorum and will not be offering services, so fencing it won't hurt. It's *always* better to put nodes into a known state, regardless of quorum.
Consider that the hung/failed node was in the middle of a write to the SAN and froze. Now imagine at some point in the future it recovers, having no idea that time passed it has no reason to doubt that it's locks are still valid so it just finishes the writes. Congrats, you could have just corrupted your storage.
_Never_ assume _anything_.
"The only thing you don't know is what you don't know."
digimer
On 11/09/13 18:24, emmanuel segura wrote:
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@xxxxxxxxxx <mailto:lists@xxxxxxxxxx>>
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
--
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
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