DNS Server Setup for ISP

Hi, we are a ISP and we currently use Google DNS IP, but we have to setup our own DNS server now, as google latency is very high in every 3-4 months.

IS this the correct tutorial to this,
https://www.digitalocean.com/communi...n-ubuntu-14-04

I have one Dell Server with with Xen, so one virtual instance of 8GB RAM and 50GB I have created.
And kept 2 public IP free for this.
Can I use this instance for DNS server and do as said in the above tutorial and setup both the IP as name servers, one for ns1 and ns2 and then setup reverse DNS records only ?

Please help!