[ClusterLabs] Load balancing, of a sort

[Antony Stone]

Hi.

I have a corosync / pacemaker 3-node cluster with a resource group which can 
run on any node in the cluster.

Every night a cron job on the node which is running the resources performs 
"crm_standby -v on" followed a short while later by "crm_standby -v off" in 
order to force the resources to migrate to another node member.

We do this partly to verify that all nodes are capable of running the 
resources, and partly because some of those resources generate significant log 
files, and if one machine just keeps running them day after day, we run out of 
disk space (which effectively means we just need to add more capacity to the 
machines, which can be done, but at a cost).

So long as a machine gets a day when it's not running the resources, a 
combination of migrating the log files to a central server, plus standard 
logfile rotation, takes care of managing the disk space.

What I notice, though, is that two of the machines tend to swap the resources 
between them, and the third machine hardly ever becomes the active node.

Is there some way of influencing the node selection mechanism when resources 
need to move away from the currently active node, so that, for example, the 
least recently used node could be favoured over the rest?


Thanks,


Antony.

-- 
I want to build a machine that will be proud of me.

 - Danny Hillis, creator of The Connection Machine

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