Service routes using data plane interface in HA

[Buck_Smooth]

I have an HA pair where I would like to use the a loopback interface for some services including DNS.  How would this work in an HA pair if they both are using the same IP address for the loopback interface?  

[PavelK · Accepted solution]

Thank you for post @Buck_Smooth

when a Firewall is HA Passive node, all data plane interfaces are suspended, therefore service route using data plane interface will not work. The standby Firewall will have to use management interface instead.

Kind Regards

Pavel 

[Adrian_Jensen]

Well... I am just pulling a HA active-passive pair out of having DNS and other services using a loopback interface on the dataplane. It worked (passive seemed to get DNS from the active, over the HA data link I assume) but having various services on a shared loopback made for funky operation (like switching between active-passive for upgrades would cause LDAP/Radius auth to fail until the system was completely back up). We also were having CPU load issues and moving DNS off the loopback and onto the management interface seemed to make a ~10-20% reduction in CPU load (combination of factors including DNS service, DNS proxy, and other services on loopback).