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Forum Discussion

thekoreanguy's avatar
thekoreanguy
Icon for Altostratus rankAltostratus
Feb 18, 2025

The blocking page did not respond on the ASM.

An HTTP POST request detected a parameter signature and blocked it. There is also a blocking event log for this request. But the client could not see the blocking page, and it seemed to be looping ...
security
VishnuGatla's avatar
VishnuGatla
Icon for Cumulonimbus rankCumulonimbus
Feb 19, 2025

The issue where the ASM blocking page is not displayed, and the client experiences looping behavior, could be caused by several factors.

Below articles might. be helpful to you. 

K78372819: HTTP request times out without returning ASM blocking page - https://my.f5.com/manage/s/article/K78372819  

K8226: The BIG-IP ASM blocking response page is not served and the connection hangs when OneConnect is enabled

https://my.f5.com/manage/s/article/K8226 

And also try with restarting the ASM service

tmsh restart sys service asm
Note: Restarting the ASM service may cause failover in a high-availability setup.

I’d suggest you open a support ticket for safeside.