Do you need to install ServiceRelease (SR) Patches on the Rim Nodes in a MultiNode environment?

[john_oll]

Question: Do you need to install ServiceRelease (SR) Patches on the Rim Nodes in a MultiNode environment or not?

Either I did not see it, or it is not included in the help, e.g.
https://help.qlik.com/en-US/sense-admin/August2023/Subsystems/DeployAdministerQSE/Content/Sense_Depl...

As far as I can tell,
- it is possible to install the SR on a Rim Node
- it is not required (e.g. if Central has an SR which the Rim Node has not, the cluster works fine)

This is RELEVANT for security vulnerabilities which get fixes by an SR, e.g.
https://community.qlik.com/t5/Official-Support-Articles/Critical-Security-fixes-for-Qlik-Sense-Enter...

Thus it should be explicitly noted in the help and if there is a security fix by SR in my opinion.

[Miguel_Angel_Baeyens · Accepted solution]

See https://help.qlik.com/en-US/sense-admin/August2023/Subsystems/DeployAdministerQSE/Content/Sense_Depl...

"Each node in a multi-node site must run the same version of Qlik Sense."

You must always patch the central node first, and then the rim nodes.

[john_oll]

As I said:
My past experience was: It actually works if you install the SR on central and not on rim nodes. (Can anyone confirm or deny this from own experience please?)
That would imply that "same version" only refers to the main version and not the SR.
Which means my question is still not answered, if it is necessary for the security fix part of the SR.

[Kunal]

@john_oll Ideally and in most of the cases all the nodes should be on same version to the patch

The reason I say so is the you will not know which part of the application does the patch update, be it Engine service, scheduler,proxy or some visualization etc.. The part it updates may be used by all nodes at some point. 

If you exactly know what all the patch is doing, then you might want to take risk.

[Miguel_Angel_Baeyens]

Never advise to have different versions between Qlik Sense central nodes and rim nodes, or between services. It is not a supported scenario and things will break.

Make sure you always plan to upgrade all the nodes in the correct order after making a backup, and always have a rollback plan if something does not work for whatever reason and you need to revert to the original version.

[anderseriksson]

General consensus is you should run the same version on ALL nodes regardless.
Yes it often works anyway with different version on rim node but update anyway.
You don't know exactly what has changed and what it affects.
If every patch stopped the rim nodes from working you would have a very difficult
task ahead of you to update ALL nodes at once if you run a larger server park.

[Miguel_Angel_Baeyens]

In all cases, for all versions, both major versions and patches must be applied to all nodes.

Doing otherwise is an unsupported scenario and known source of issues, even if "it works".

You must always patch the central node first, and then all the rim nodes despite their role or services installed.

Always backup your environment first (here is how: https://help.qlik.com/en-US/sense-admin/November2023/Subsystems/DeployAdministerQSE/Content/Sense_De...). Always.