SSL decryption inconsistency

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SSL decryption inconsistency

L2 Linker



I have enabled decryption on a small group for testing purposes. I have a simpel 2 rule setup, first exluding financial, health and custom white listed and then decrypt everything else.


I have a hard time finding out why the same site in the same browser on different pc's behave differently. For example my colleague got ERR_SSL_PROTOCOL_ERROR on with chrome while at the same time it was ok on my pc, also with chrome. How do I examine those kinds of errors?


Further, I lack more how to's and best practises in general regarding ssl decryption. Like how you should maintain the firewalls list of trusted CA's, both changed and revoked CA's. 


Any tip you have about seting it up and adminstering ssl decryption is appreciated!





L5 Sessionator

what is the PA-OS of  the firewall?

L5 Sessionator

We run 6.0.10 on 3020 in passive/active HA.


There are some helpful stuff in that link but most of it for the setup.


Could there be mismatches between certs in windows (7/8) and in palo?

A couple of things from my own experience with testing decryption (6.0.14 on the GWs) -


- After changing the decryption policy it can need to rebuild the certificate cache as sites are accessed, so you are best to leave off testing  for 5 mins or so otherwise you can get odd results


- Browser cache can also produce different results (yes - I know SSL results shouldnt be cached, just passing on what I found) so if you get odd results be sure to CTL + F5


Might help ?



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