We had 2 PIX firewall (525-UR) in Failover mode and recently i added third 1 Port NIC card on the Pix Firewalls(total of 8 ethernet ports 4port +1 port + 1port+1 inside and 1 outside) . As soon as I added the new NIC card on Firewall it crashed and second one became primary. After which secondary Firewall crashed and tried to switch over to Primary and it kept toggling untill i removed the cards from both Firewalls.
Now i have reverted back to my previous setting with (7 FE ports 4port+1port+1 inside and 1 outside) and FWs are working fine. Is their any known bugs or reason with 525 FW with 8 NIC ports working in Failover mode ?