I have website that run over the WAF with (LTM + ASM ) , Recently I'm facing slowness issue when trying to access the portal through WAF but if i tried to access it directly from the server it is fast ( bypass WAF )
so what i have to do to investigate the root cause of slowness ?
Check the ASM CPU as usually this can cause the issues as the ASM causes a lot of CPU, especially if you making many policies that are still in learning mode:
Carefully read this article:
Also it could be that it is LTM issue with bad tcp or http profile, so disable the ASM policy and test the website only with LTM load balancing:
As a final test if nothing is seem to help do tcpdumps to see if the F5 is introducing the slowness as when you bypass the F5 device you can also also bypass other network devices that are near the F5 device that can cause issues (the switch connected to the F5 device that is after or before the f5 device for example):