I have 2 pairs of pri/sec firewalls placed at remote locations. Each pair is working in a failover mode, that is, SITE-1-FW1 is being synchronized with SITE-1-FW2, and same is the case with SITE-2 firewalls.
Now, i am planning to upgrade SITE-2 firewalls, and for that i need to make sure that both pairs (on SITE-1 and SITE-2) should have up-to-date config. SO that i will route my traffic to SITE-1, will upgrade firewalls on SITE-2, and then will do the same for SITE-1. My question is, who can i automate this synchronization process, on firewalls placed at remote location.