HA pair

What IP ( self IP of active one or Floating IP)will be used when we enable SNAT auto ? if you've got configured floating IPs it will prioritise the floating IP of the egress interface, then any other floating IP before using the non-floating IPs. See https://support.f5.com/kb/en-us/solutions/public/7000/300/sol7336.html

What is the role of having floating IP at External VLAN and in which scenario, it’s used? - Sometimes you might need a route pointing to your bigips from an upstream device. this is when you may use this.

What IP f5 (self IP of active one or Floating IP) uses to probe servers health check? Non-floating self IPs on both bigips in a pair.

What are all objects will be failover to passive device when active one will be down ? Listener objects like Virtual Servers/Addresses etc..

When we do sync in active appliance, is that all configurations replicated to standby appliance or still we have some objects or configurations, which will not be replicated to standby appliance? Most configuration is synced except for configuration which is bigip specific like non-floating self ips.

Hope this helps,

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