This may not be the answer you want to hear as it's a bit of a fudge I think, but I wanted to share an idea with you (as I don't believe there is any supported way of doing this, i.e. having a running
keepalived process reload it's config).
You could manually add the IP's to the
keepalived interface on the VRRP master using CLI, so assume server1 eth1 is 192.168.0.1 and server2 eth1 is 192.168.0.2, and they both have 192.168.0.254 in
keepalived. On server1;
sudo ip a a 192.168.0.253/24 dev eth1
The master now has the additional IP(s).
On server2, make the changes to
keepalived config, add in the new IPs, add them under virtual_ipaddress_excluded, as per this SF query.
keepalived process on server2, the backup server.
Now add the IP(s) into server1
keepalived confif but don't bounce the daemon, as that will cause downtime. If/when the day comes your master
keepalived box enters the fail over state and the server2 becomes master, bounce
keepalived on server1 then to reload the config (assuming you're not using preempt, server1 will now wait to become master again, and both boxes have the new IP(s) configured).
That is the only way I can see to do this. I'd like to hear a method for making a running
keepalived reload it's config if anyone has such a method.