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Forum Discussion

sandy16's avatar
sandy16
Icon for Altostratus rankAltostratus
Jun 20, 2016

illegal cookie length: ASM violation

HI ASM experts, I am seeing traffic getting blocked due to the "Illegal cookie length violation" . System configured: 8192 bytes, received 8452. I am running 11.5.1 HF7. I tried to increase the cook...
ASM Advanced WAF
security
Hannes_Rapp's avatar
Hannes_Rapp
Icon for Nimbostratus rankNimbostratus
Jun 20, 2016

8192 Is indeed the maximum and I think you only have 2 workarounds - disable the violation, or write a custom iRule. Disabling the violation itself would probably make the most sense here.

Go to policy blocking settings, and un-tick the 'learn/alarm/block' boxes under 

Illegal cookie length
violation. Save and apply changes.

MSZ's avatar
MSZ
Icon for Nimbostratus rankNimbostratus
Jul 23, 2017

What about 2048 bytes