Here is the structure we have, 3 servers in location A (172.22.25.X) and 3 servers in location B (192.168.140.X). One of the 3 servers in each location creates an SSL connection to the other 4 servers, like this:
A1 connects to A2, A3, B2 and B3 B1 connects to A2, A3, B2 and B3
When A1 connects to any of the servers, the SSL Handshake takes less than 300ms.
When B1 connects to A2 and A3, the SSL Handshake takes less than 300ms.
But when B1 connects to B2 or B3, the first time it takes around 9 seconds for the handshake to be finished. Following requests again take less than 300ms for a short while (a minute or two), and then back to the 9 seconds issue.
All 6 servers have the same software on them, running on the same OS (Windows Server 2008 R2 64 bit).
We tried all kinds of changes (enabling and disabling Windows Firewall, removing the antivirus software, changing the switch) but still the same issue continues, and we are out of ideas what it could be causing it.