For more information regarding the security incident at F5, the actions we are taking to address it, and our ongoing efforts to protect our customers, click here.

Forum Discussion

rolf's avatar
rolf
Icon for Cirrus rankCirrus
Oct 19, 2018

TCL error: _cgc_pick_clientside

Hi,   in an ASM-LTM (Perimeter) Setup I see frquently the following logs:   ***err: tmm3[19962]: 01220001:3: TCL error: _cgc_pick_clientside - unknown cgc sni: f5-bei1.xxxx.xx (line 49) invoke...
application delivery
ASM Advanced WAF
clientssl
LTM
security
sni
ssl
Steve_MC's avatar
Steve_MC
Icon for Nimbostratus rankNimbostratus
Feb 10, 2021

I found this page searching for an answer to the exact question  was asking, kept searching, and was eventually able to find this Support Solution:

 

https://support.f5.com/csp/article/K54469707

 

It mentions that this is actually a big3d error and sure enough, when I checked /var/log/gtm I found SSL Error messages that matched up with these /var/log/ltm messages. Even better, the /var/log/gtm messages list the IP that these connections are coming from, which in my case turned out to be one of our internal security appliances doing a scan.