Mar 27, 2026 - For details about updated CVE-2025-53521 (BIG-IP APM vulnerability), refer to K000156741.

Forum Discussion

pdh's avatar
pdh
Icon for Nimbostratus rankNimbostratus
May 13, 2014

Conditional caching using an iRule

Hi, I am trying to conditionally disable ramcache from within an iRule, based on an HTTP class, but it is not behaving as I would expect. I am hoping someone here might be able to explain why. Ve...
application delivery
devops
irules
LTM
pdh's avatar
pdh
Icon for Nimbostratus rankNimbostratus
May 14, 2014

And the answer was: Caching was working just fine, but the client I was using, even when asked to force-reload images was apparently still sending If-Modified-Since. So the correct logic was being triggered, and the logs verified that, but no content was actually being retrieved from the servers to populate the cache.

 

Combined with a logical error in the original iRule that I had already fixed (which set me off on this path in the first place), I have been chasing a ghost.

 

Complete PEBCAK. I am going away now to try to find a copy of "HTTP for Dummies".

 

JRahm's avatar
JRahm
Icon for Admin rankAdmin
May 15, 2014
glad you found the issue. and thanks for the new acronym! Hadn't heard that one, I always use ID-10-t. :) There's so much on the stinkin' stack to learn between layers 1 and 7, anyone bored in this industry is wasting potential.