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Forum Discussion

THE_BLUE's avatar
THE_BLUE
Icon for Cirrostratus rankCirrostratus
May 17, 2021

troubleshoot slowness issue in WAF

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 fas...
application delivery
ASM Advanced WAF
LTM
Nikoolayy1's avatar
Nikoolayy1
Icon for MVP rankMVP
May 17, 2021

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:

 

 

https://support.f5.com/csp/article/K58571155

 

 

Carefully read this article:

 

 

https://support.f5.com/csp/article/K47045262

 

 

 

 

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:

 

 

https://support.f5.com/csp/article/K03553427

 

https://support.f5.com/csp/article/K02408315

 

https://support.f5.com/csp/article/K5379

 

 

 

 

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):

 

 

 

https://support.f5.com/csp/article/K411

 

https://support.f5.com/csp/article/K13637