03-11-2022 08:31 AM
Thank you all for help, it turns out that on source firewall PA-440 I allow traffic for Panorama Application on its default port 3978, but in firewall monitor I found that the flow is recognized as ssl on port 3978 and this was blocked.
I was thinking that once there is Panorama app it will be match and didn't check this, but I was wrong. 🙂
I had simmilar issue today on another firewall in Data Center where we had rule for WinRM (microsoft-remote-management), which was working fine before but now after some updates it is recognized as web-browsing on the WinRM port 5985.
So the solution is to not trust the Palo Alto application matching and always check the flows.