Some vizualisations are not available on Apps when Central Node is failed over

[Proginov]

Hi,

We encounter an issue in a multiple nodes configuration on Qlik Sense Enterprise on Windows when the Central Node (called "Primary Central Node" in our configuration) fails and the failover node (called "Secondary Central Node") switch to Master.

Everything seams to run fine, but some extensions are not available on the Hub on rim nodes (we have 4 proxy nodes) with the message:

"Vizualisation not found on server. This extension is not available'

As these extensions are needed to use our Apps, our customers are locked until we rollback to the Primary Central Node.

It is quite a shame that failover don't work as expected, just partially, because it is no use in the way it works at the moment.

We have tested reimport of the extensions both with Primary Central Node as master or with Secondary Central Node as master, with no luck.

Our config is QSEoW May 2025 Patch 4 (Patch 6 tonight), with:

• 1 Central Node (Primary Central Node)
• 1 Failover Node (without customer connection) (Secondary Central Node)
• 2 Scheduler Nodes (SCHD01 and SCHD02)
• 5 Proxy Nodes ( PN01/02/03/04/05), PN05 is only for testing purposes, so no customer connection
• 1 dedicated File Server Cluster for Repository
• 1 dedicated PostgreSQL server for Repo DB

We have the issue even in previous versions.

Our problem is more than 4 years old, but is really annoying us now concerning SLA.

Thanks in advance for your help.

[Rakesh_HB]

Hi @Proginov ,

Are these extensions accessible from the failed-over node?

Extensions or any objects used in Qlik Sense must be accessible to all the Qlik Sense nodes.

Or does it work intermittently?

Thanks!

[Proginov]

Hi @Rakesh_HB ,

From a network point of view, yes, the objects are (or should be) reachable as the Shared Repository is on a separate FileServer Cluster (not on the Primary Node).

The thing is : we import extension from the Managment Console, everything is OK, but when we fail over, the vizualisations are not working anymore (everytime, it does not work at all).

When back to the Primary Node, it is OK.

So either we don't import it the right way (but as there is just one button on the Managment Console to do it, with no option, that shoud be strange), or the way the extensions are registered is not good and don't use the Shared Persistent Storage but a local directory on the Primary Node instead.

I tried to serach and read the maximum information I could about Qlik Sense failover setup, but everything is quite obvious, and even with double checking, I don't see anything we did not follow correctly.

Anyway, thank you for your help 🙂

[Rakesh_HB]

Hi @Proginov 

Do you have any Custom security rules related to Extensions?

Also, review the user access and security rules for the affected extension in the QMC under Extension properties.

Have you tried placing the extensions in the Shared folder -

C:\<Sharedpath>\qliksense\StaticContent\Extensions?

You can also try this solution

[Proginov · Accepted solution]

Hi @Rakesh_HB,

Sorry to be so late to answer.

We don't have any Custom Security rules related to Extensions and the User Access and Security Rules are correct.

Our extensions are already in the path you mentioned.

We resolved our problem by installing a new node,called FON: Fail Over Node,with all services installed, and promoted it as failover. We then deleted our secondary node (In "Nodes" tab of the QMC)
And it worked, even if the obsolete and deleted Secondary Node keeps on showing in the "Engine Health" tab of the QMC.