[Linux-cluster] quorum

[Digimer]

Share your configuration, please.

On 03/31/2013 02:51 AM, Prathyush wrote:
> Any Idea ?
>
>
> On Sat, Mar 23, 2013 at 3:41 PM, Prathyush <prathyush.r at gmail.com
> <mailto:prathyush.r at gmail.com>> wrote:
>
>     I have the below scenario,
>     I have made the first node down the service failover to second
>     node,then I switched off second node ,service again swiched to third
>     node,the quorum was not lost,it adjusted automatically
>
>     On Mar 22, 2013 9:11 PM, "Digimer" <lists at alteeve.ca
>     <mailto:lists at alteeve.ca>> wrote:
>
>         This is correct.
>
>         Quorum needs "50% + 1" of the votes. So in Prathyush's cluster
>         of 3 nodes/3 votes;
>
>         3 / 2 == 1.5 rounded up is 2.
>
>         So once the second node shut down, quorum was lost. With quorum
>         lost, the remaining node will stop all of it's clustered
>         services because it can no longer be sure what the other nodes
>         are doing. For example, the other two nodes might turn back on,
>         fail to connect to the one remaining node, decide they have
>         quorum and start clustered services. This would lead to a split
>         brain.
>
>         If you want a 3-node cluster to work with just one node,
>         consider adding a quorum disk, assuming you have a SAN. This
>         would add 2 votes to the cluster. So the new math would be;
>
>         5/2 == 2.5 rounded up to 3.
>
>         The quorum disk would give it's two votes to the remaining
>         single node for a total of 3 votes, thus giving it quorum and
>         allowing it to operate on it's own.
>
>         digimer
>
>         On 03/22/2013 03:16 AM, emmanuel segura wrote:
>
>             Hello
>
>             If i understand well, you 3 node(3 total votes) and you
>             poweroff 2, 3 -
>             2 = 1(quorum loss) remain less 50% of votes
>
>             can you show your config and your log, without it's so hard
>             help you
>
>             Thanks
>
>             2013/3/22 Prathyush <prathyush.r at gmail.com
>             <mailto:prathyush.r at gmail.com> <mailto:prathyush.r at gmail.com
>             <mailto:prathyush.r at gmail.com>>__>
>
>                  HI,
>
>
>                  I have 3 node  cluster with 1 vote each ,and  decided
>             to shut down
>                  the 2 nodes for  maintenance .
>                  When a proper power off /init 0 given to two of the
>             nodes ,i never
>                  loses the quorum
>                  When i am making  force power off (switching off the
>             power/pulling
>                  the power cable) quorum  was lost and services failed
>             in the third node.
>                  why this is happening... any idea
>                  --
>                  /*Regards,
>                  Prathyush*/
>
>
>
>         --
>         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?
>
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>
>
>
>
> --
> /*Regards,
> Prathyush*/
>
>


-- 
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?