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Forum Discussion

Peter_Baumann's avatar
Peter_Baumann
Icon for Cirrostratus rankCirrostratus
Nov 16, 2022

APM sends local favicon.ico to client instead of fetching it from the backend

This behavior seems to be since 16.1.2 and 16.1.3 version upgrade. The APM is sending the local version of favicon.ico to the client and not the version of the backend after the session has establish...
application delivery
BIG-IP Access Policy Manager (APM)
f5
Peter_Baumann's avatar
Peter_Baumann
Icon for Cirrostratus rankCirrostratus
Feb 01, 2023

Hi Lucas_Thompson ,
Unfortunately it still doesn't work. But your iRule seems to do the right thing, thank you for that!
When I don't have a session I get the 404 back as seen in devtools from the browser.
When I have a session I get the favicon.ico but not from the backend.
It still uses the default icon from APM:

I have seen this now at other customer installations. For me this seems to be a bug in APM not sending the favicon.ico from the backend to the client.

Thanks,
Peter

Lucas_Thompson's avatar
Lucas_Thompson
Icon for Employee rankEmployee
Feb 01, 2023

Thanks for the quick feedback, it sounds like we're on the right track.

So, in your situation where APM doesn't know what backend to use because it's dynamic and the user has not yet logged in, what favicon (or HTTP error or whatever?) should APM send? We can make the iRule do anything we want, as long as we can precisely define what we want it to do.

By default APM sends its own favicon because the browser requests it right away on the site BEFORE logging it at all, and we definitely wouldn't want to leak files from the backend prior to APM auth, at least by default.