I have two NICs.
I will have to change NS2 IP since rDNS can only be set to IP that has been directly set to network card.
eth0 currently has xx.xx.xx.xx (with rDNS) - GateWay pp.pp.pp.pp
eth1 currently has yy.yy.yy.yy (with rDNS) - GateWay pp.pp.pp.pp
now I must change eth1 yy.yy.yy.yy into hh.hh.hh.hh
That means nameserver2 IP changes into hh.hh.hh.hh and IP yy.yy.yy.yy would go down right after I change it.
After the change it would look like:
eth0 will still have xx.xx.xx.xx (with rDNS) - GateWay pp.pp.pp.pp [I want to make 100 websites to use this GateWay and this NIC]
eth1 will have hh.hh.hh.hh (with rDNS) - GateWay tt.tt.tt.tt [I want to make 200 websites to use this GateWay and this NIC]
Setting smaller TTL for nameserver2 few days before I make the change could make it propagate faster?
Or would WHM allow me to add IP addresses with GateWay tt.tt.tt.tt even when both NICs use GateWay pp.pp.pp.pp ?
I mean in Switch both gateways are on same VLAN. - if it does allow this, I dont have to change nameserver ip.