[ClusterLabs] Recovering after split-brain

[Digimer]

On 20/06/16 09:30 AM, Nikhil Utane wrote:
> Hi,
> 
> For our solution we are making a conscious choice to not use
> quorum/fencing as for us service availability is more important than
> having 2 nodes take up the same active role. Split-brain is not an issue
> for us (at least i think that way) since we have a second line of

Then wouldn't it be a lot better to just run your services on both nodes
all the time and take HA out of the picture? Availability is predicated
on building the simplest system possible. If you have no concerns about
uncoordinated access, then make like simpler and remove pacemaker entirely.

> defense. We have clients who can connect to only one of the two active
> nodes. So in that sense, even if we end up with 2 nodes becoming active,
> since the clients can connect to only 1 of the active node, we should
> not have any issue.
> 
> Now my question is what happens after recovering from split-brain since
> the resource will be active on both the nodes. From application point of
> view we want to be able to find out which node is servicing the clients
> and keep that operational and make the other one as standby.
> 
> Does Pacemaker make it easy to do this kind of thing through some means?
> Are there any issues that I am completely unaware due to letting
> split-brain occur?
> 
> -Thanks
> Nikhil


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