topic Re: loadbalancing rule to run an app on only specific rim node in Management & Governance

loadbalancing rule to run an app on only specific rim node

ArifShah — Tue, 17 Dec 2019 08:39:18 GMT

Hi,

I have two nodes and central and rim node are both running schedulars. I am testing the load balancing rule to test that an app only runs on the specific rim node

I tried to create the load balancing rule

((node.name="qs102" and resource.name="License Monitor"))

In the resource filter, I selected *

However, it seems like this rule is not working and the app is still reloading on the central node

Any clues how to fix this?

Re: loadbalancing rule to run an app on only specific rim node

rzenere_avvale — Tue, 17 Dec 2019 08:48:33 GMT

Goodmorning @ArifShah ,

please consider that there is a default load balancing rule called ResourcesOnCentralNode (which cannot be disabled) that will always balance resources on central node... So, if you leave the scheduler of central node as master and slave (which is your current configuration), you'll most likely end up reloading always some apps on the central node
I would suggest, for test purposes, to add another node, disabling the load balancing rule called ResourcesOnNonCentralNodes (which by default load balances all resources on all nodes, except for monitoring apps which will always be on the central node) and then create a new rule fitting your purposes

Hope this helps,
Riccardo

Re: loadbalancing rule to run an app on only specific rim node

ArifShah — Tue, 17 Dec 2019 10:14:02 GMT

Hi Riccardo,

Many thanks for the answer. One more question related to this. We have a central node that is both master and slave. We have another node schedular 2 that is also used for reloads. We use the default load balancing so some of the reloads run on central node and some run on schedular2 node

Then we added schedular 3 node to the cluster. I wrote the the load balancing rule for the schedular 3 but forgot to enable the schedular service in the node schedular3.

Resource filter = app_*

((node.name="eudvmmsqs102" and resource.name="0Equipment"))

In morning, when I came, all the reloads ran on central node. No reload went to schedular2 even though the load balancing did not mention anything about schedular2

I would expect that only schedular3 node should not have run any reloads but why was there an impact on schedular2 node?

Regards

Re: loadbalancing rule to run an app on only specific rim node

rzenere_avvale — Tue, 17 Dec 2019 13:09:32 GMT

That is due to the fact that central node's scheduler is both master and slave.
The only way to avoid that is to set the central node's scheduler as master, but that way no reload will be performed on the central node (so you'll need to disable the load balancing rule ResourcesOnNonCentralNodes and create a new one - or modify directly the load balancing rule ResourcesOnNonCentralNodes)