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TJ_Vreugdenhil's avatar
TJ_Vreugdenhil
Icon for Cirrus rankCirrus
Aug 09, 2016

ASM TSxxxx Max Cookie Size

We have an environment where the WCS servers have a cookie size crossing threshold of 8Kb per request. The TSxxxx F5 ASM cookies take more then half of this threshold. I understand there is a way to delete the TS cookies using an iRule before they make it to the WCS servers, but we are worried about the statement in the Solution article that says: "could introduce noticeable latency"

 

I was looking into the Advanced System Variables page on the ASM and was hoping to find a variable to lower the max size of these cookies, but didn't see one.

 

Does anyone know if it's possible to lower the cookies size for these two values in 11.6.0 HF6:

 

Main ASM cookie: TSxxxxxxxx

 

ASM Frame cookie: TSxxxxxxxx_d

 

https://support.f5.com/kb/en-us/solutions/public/6000/800/sol6850.html

 

https://support.f5.com/kb/en-us/solutions/public/13000/600/sol13693.html

 

ASM Advanced WAF
security

1 Reply

  • Chris_Grant's avatar
    Chris_Grant
    Icon for Employee rankEmployee
    Aug 11, 2016

    You really can't. The ASM cookies include a hash of the other cookies in the request, and as such their size is directly influenced by the size of all the other cookies. None of the data included in the ASM cookies is fluff or padding, so there is no way to reduce the size without losing some kind of functionality. As a result, we don't let you do that.