I 'had' just a single VPS with nameservers ns1 & ns2.mydomain.com. I've now taken a VMCloud package as I need space etc.
Ultimately I will carefully transfer all accounts from my VPS to Cloud but in the short term I'm running both.
In the new WHM on Cloud I have set hostname bla.domian nameservers as ns3 & ns4.mydomain.com with the two new ip addresses.
Question is do I need to do anything else - eg where mydomain.com is registered? I want ns1 & 2 point to VPS and ns3 & 4 to point to Cloud.