topic Re: How to prevent usage failover node by schedulers tasks in Management & Governance

How to prevent usage failover node by schedulers tasks

BuTbka — Sat, 16 Nov 2024 00:19:36 GMT

We have two failover nodes which are weak(2 cores, 16gb ram).
We have planned to use them as active and passive proxies for failover cases. On the active node scheduler have option with value primary. But on the passive - secondary. And that is why on the passive node tasks overload server. How we can prevent to run tasks on the passive node?

Re: How to prevent usage failover node by schedulers tasks

Sooraj_Suresh — Sat, 03 Apr 2021 05:46:13 GMT

Are tasks running on both active and passive or is it that the tasks run only on the passive and its getting overloaded. Have you implemented load-balancing rules for nodes?

To dedicate applications to reload on specific node(s), you will need to change the default load balancing rule in the QMC.

Please find an example using custom properties: https://adminplaybook.qlik-poc.com/docs/asset_management/apps/review_pinning_load_balancing.html

When running task in chain, the entire chain will run on the same Scheduler node.

You may also refer to the below article.

https://support.qlik.com/articles/000038755

Hope the above suggestion helps!

Best Regards,

Sooraj Suresh

Re: How to prevent usage failover node by schedulers tasks

BuTbka — Mon, 05 Apr 2021 08:31:50 GMT

@Sooraj_Suresh wrote:
Are tasks running on both active and passive or is it that the tasks run only on the passive and its getting overloaded. Have you implemented load-balancing rules for nodes?

Thanks for reply! Tasks are running on passive nodes with scheduler only. We need to exclude one of them. But we cannot, because it in failover mode.

To dedicate applications to reload on specific node(s), you will need to change the default load balancing rule in the QMC.
Please find an example using custom properties: https://adminplaybook.qlik-poc.com/docs/asset_management/apps/review_pinning_load_balancing.html

I only found information about load balancing an application, not a task

Re: How to prevent usage failover node by schedulers tasks

Bastien_Laugiero — Tue, 06 Apr 2021 06:53:56 GMT

Hello,

In Qlik Sense you cannot load balance a task directly, however you can load balance the application associated to this task.

So this ling https://adminplaybook.qlik-poc.com/docs/asset_management/apps/review_pinning_load_balancing.html still applies to your case.

If you set your load balancing rule to exclude the specific application associated to your task, then the scheduler slave will not try to run it and the task will be launched on another "Slave" were this application is available.

Now regarding the failover candidate, if your "passive" node becomes Central then this node will automatically get access to every application (and therefore be able to run any task) and this cannot be changed even with load balancing rules.

So perhaps having the failover candidate set on a Scheduler node is not the best option in your case. You could perhaps set it on another node such as a proxy or on a dedicated smaller machine.

Hope this helps!

Re: How to prevent usage failover node by schedulers tasks

BuTbka — Tue, 06 Apr 2021 08:06:39 GMT

@Bastien_Laugiero wrote:
So perhaps having the failover candidate set on a Scheduler node is not the best option in your case. You could perhaps set it on another node such as a proxy or on a dedicated smaller machine.

Thanks for reply! But I cannot set failover node without scheduler service:

Re: How to prevent usage failover node by schedulers tasks

Bastien_Laugiero — Tue, 06 Apr 2021 08:22:14 GMT

Hello,

Yes you are correct, I missed that part. I think this scenario cannot be properly handled in the current capabilities provided by the scheduler and failover functionality.

I'd suggest to log an idea on this page https://community.qlik.com/t5/Suggest-an-Idea/idb-p/qlik-ideas