502 error when shifting between Studio and Portal

Unknown

502 error when shifting between Studio and Portal

Unknown

Stumbled upon an error while implementing a Decisions cluster behind a load balancer. It was a bit tricky to trouble shoot so I thought Ill share.

Basically I was getting a 502 Bad Gateway error when shifting between Studio and Portal. It worked again if I just reloaded the page. It usually happend the first time I shifted, and after that it worked fine for a while.

This only occured for users that was logged in with SAML SSO, not local users.

After troubleshooting I found that the load balancer by default had a maximum number/size of headers and Decisions exceeded that threshold when redirecting between portal and studio. (Probably headers that are related to the SSO)
The solution for HAProxy was configuring tune.http.maxhdr to a larger number (Im using 500 and it seems to work, but a to large number could affect memory usage. So please tune this to your implementation). If you are using Nginx you should look into the buffer-size parameter.

Hope this helps
[i]edited by Vigersand on 1/13/2023[/i]