how Setup NS1/NS2 For My VPS?
Solution 1:
I would probably leave the DNS (primary and secondary) pointing at the VPS provider's nameservers and just update your DNS records (www = w.x.y.z) with whoever hosts your domain name.
Since you only have 1 IP address assigned I don't think you intend to host your own DNS nameservers. Better just remove the DNS role from the server.