/etc/hosts has your hostname information
/etc/named.conf has the path to the domain's DNS zone entries
/var/named/domainname.com.db has the DNS zone entries for the domain name
/var/nameserverips has the name server information
You can edit all those files from WHM, you do not need to edit them manually unless something goes wrong.
If you want to do edit it via SSH you can just use pico or nano.
MediaLayer, LLC - www.medialayer.comLearn how we can make your website load faster, translating to better conversion rates for your business!
The pioneers of optimized web hosting, featuring LiteSpeed Web Server & SSD Storage - Celebrating 10 Years in Business