Gluster users - Aug 2015 - Why is it not possible to mount a replicated gluster volume with one Gluster server?

On Monday 31 August 2015 10:42 PM, Atin Mukherjee wrote:
>  > 2. Server2 dies. Server1 has to reboot.
>  >
>  > In this case the service stays down. It is inpossible to remount the
> share without Server1. This is not acceptable for a High Availability
> System and I believe also not intended, but a misconfiguration or bug.
> This is exactly what I gave as an example in the thread (please read
> again). GlusterD is not supposed to start brick process if its other
> counter part hasn't come up yet in a 2 node setup. The reason it has
> been designed in this way is to block GlusterD on operating on a volume
> which could be stale as the node was down and cluster was operational
> earlier.
For two node deployments, a third dummy node is recommended to ensure 
that quorum is maintained when one of the nodes is down.

Regards,
Vijay

I understand. So my setup is maybe wrong. Vijay, could you please explain
how this dummy node setup would look like?

Do you recommend to setup a glusterd on node3 and replicate to 3 servers?
In my understanding this would significantly reduce performance as files
have to be replicated 3 times. Would it be possible to mount the volume if
2 of 3 glusterd servers are live?

2015-08-31 19:41 GMT+02:00 Vijay Bellur <vbellur at redhat.com>:
> On Monday 31 August 2015 10:42 PM, Atin Mukherjee wrote:
>
>>  > 2. Server2 dies. Server1 has to reboot.
>>  >
>>  > In this case the service stays down. It is inpossible to remount
the
>> share without Server1. This is not acceptable for a High Availability
>> System and I believe also not intended, but a misconfiguration or bug.
>> This is exactly what I gave as an example in the thread (please read
>> again). GlusterD is not supposed to start brick process if its other
>> counter part hasn't come up yet in a 2 node setup. The reason it
has
>> been designed in this way is to block GlusterD on operating on a volume
>> which could be stale as the node was down and cluster was operational
>> earlier.
>>
>
> For two node deployments, a third dummy node is recommended to ensure that
> quorum is maintained when one of the nodes is down.
>
> Regards,
> Vijay
>
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On 08/31/2015 10:41 AM, Vijay Bellur wrote:
> On Monday 31 August 2015 10:42 PM, Atin Mukherjee wrote:
>>  > 2. Server2 dies. Server1 has to reboot.
>>  >
>>  > In this case the service stays down. It is inpossible to remount
the
>> share without Server1. This is not acceptable for a High Availability
>> System and I believe also not intended, but a misconfiguration or bug.
>> This is exactly what I gave as an example in the thread (please read
>> again). GlusterD is not supposed to start brick process if its other
>> counter part hasn't come up yet in a 2 node setup. The reason it
has
>> been designed in this way is to block GlusterD on operating on a volume
>> which could be stale as the node was down and cluster was operational
>> earlier.
>
> For two node deployments, a third dummy node is recommended to ensure 
> that quorum is maintained when one of the nodes is down.
>
> Regards,
> Vijay
Have the settings changed to enable server quorum by default?