Add additional IP Addresses

I am behind a UTM appliance so I have NAT enabled. I would like some domains to have their own IP address. I have 192.168.1.10 specified for Default IP, Shared IP and NAT'ed IP.

I know how to add additional IP addresses to the server but how do I set up the config files for each domain?

I added IP address 192.168.1.11 to the server and selected it for a particular user account. I want to use this IP address for a specific domain. I am using Apache, NGINX Reverse Proxy and Varnish. Do I have to manually change the IP address in all three server's config files? What about the Varnish config files? Do I have to create/add an additional secret for the new IP? What code do I add/edit and to what Varnish config file(s)?

Also, when I use Apache Settings->Rebuild Virtual Hosts, it uses 192.168.1.10 for all domains even though I have 192.168.1.11 specified for one of the user accounts. The Rebuild Virtual Hosts tool isn't designed to pull/insert the IP address assigned to each user account???