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Forum Discussion

Mohan's avatar
Mohan
Icon for Altostratus rankAltostratus
Sep 17, 2019

SSL handshake fail after software upgrade from 12.1.2 to 13.1.1.5

we see lot many SSL handshake fail warnings in ltm logs for a cleint SSL enabled VIP traffic after software upgrade from 12.1.2 to 13.1.1.5,      
BIG-IP
LTM
security
Nathan_F__F5_'s avatar
Nathan_F__F5_
Icon for Employee rankEmployee
Sep 18, 2019

Hi Mohan,

 

Does the client SSL profile use the "DEFAULT" cipher string? If it does then that may be the reason for the handshake failures. The default ciphers have changed between versions. For more information please take a look at the following article.

 

K13156: SSL ciphers used in the default SSL profiles (11.x - 13.x)

https://support.f5.com/csp/article/K13156

 

-Nathan F