[sheepdog-users] vdi stalled with 2 out of 3 node online

[Liu Yuan]

On Wed, Mar 26, 2014 at 09:20:32AM +0100, richter at ecos.de wrote:
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> Hi,
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> last Friday one of my three nodes has left the cluster (I don't have any
> idea why). A "dog node recovery" shows "Waiting for other nodes to join
> cluster".

I guess you are using corosync, which is said to be easily running into network
partition problem.

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> The other two nodes worked as expected. On Monday evening one VM stopped
> working (also stop and start of the VM didn't change anything).
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> Now I have restarted sheepdog on the node that was not joining the cluster
> anymore, it joined the cluster, does a recovery and the VM on the other
> node, that didn't worked before, now works as expected (and _
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> _ data was lost :-)
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> If I a have a cluster with three node and number of copies is set to three,
> why does a VM stop working, if two nodes up and running? Moreover, it is
> strange that it stopped after three days.
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If you don't add '-t' for 'dog cluster format', sheepdog cluster will run without
any problem even if your nodes number < redundancy number.

Thanks
Yuan