Unable to connect to the Qlik Sense engine error displayed on Qlik Sense Hub

[micheledenardi]

Dear All,

i have two Qlik Sense June 2020 Patch 3  environments, Dev/Test (1 node) and Production (3 nodes).

When i'm at home in remote working everything goes well  when i use Production env, so i can connect Hub, develop and play with analysis and use QMC as i be at office, without any difference.

Everything works well also when i use QMC on Dev/Test env but if i try to access any analysis in the Dev/Test Hub this error is raised:

This only happens on Dev/Test Hub, QMC works perfectly.

I search on the net and i found this thread where they suggest to use Qlik Sense Websocket Connectivity Tester to check if something is not working with the connection between qlik server and client.

I run the tester and the result is this:

Any ideas on how to solve red ones?

Max connections entry in the %ProgramData%Qlik\Sense\Repository\PostgreSQL\<version>\postgresql.conf are configurated correctly. Tried to increase this parameter but nothing change.

[Bastien_Laugiero · Accepted solution]

Hello, 

This would suggest that the secure websocket protocol (WSS) is blocked when connecting to the Dev/Test Hub. 

The QMC does not use WebSocket which explains why it is working fine. The other interesting point is that Prod is working which suggest that you may go through different network or network equipment (NLB, Proxy,...) when accessing Prod compared to Dev/Test.

You may need to reach out to your IT Team to find out which equipment might be blocking WSS.

Hope this helps!

[Lokeshb31]

I went through many articles, each article was explaining about web socket communication but was not clear which port/flow is getting blocked. We are using multi node deployment i.e. central node, engine, schedule and 3 proxy nodes (3 app nodes, 3 web nodes). We were able to investigate that port 4747 (Engine) was blocked between app nodes and web nodes. We opened the port and it all started working fine. 

[Zhumabay]

Hi
lease tell me how did you do it?