I manage a server without a cpanel, I installed Webmin on it. And under Bind settings I have these zones:
"Root zone"
"0"
"0000::1"
"127.0.0.1"
"mydomain.com"
"localhost"
"localhost.localdomain"
I am wondering if is safe to remove these zones and only leave "root zone" and "mydomain.com". I am not sure why they are there but on another server I only have these two left and seems to work ok.
If the server is only authoritative (i.e. serving your domain to third parties) you may safely remove those zones.
If the server is providing recursive DNS lookup service to any client (including to itself[*]) then they should remain to prevent queries for those potential local zones going out to the wider internet.
[*] i.e. if
/etc/resolv.conf
contains127.0.0.1
They are there in case something looks up those names and doesn't have entry in their hosts file the way they're supposed to. I don't know what "0" is, but the localhost and loopback IP zones should be there.