How to change your hostname

The hostname is the name you give your server.  It needs to be a fully qualified domain name, meaning it needs to resolve, and should resolve to your server IP.

The value of your hostname should be in the form similar to:

server.domain.com

where you run/manage domain.com (usually something like your webhost domain).  The value "server" or something like that needs to be in front of it.  (ns1 or www are both valid).   You cannot use just "domain.com" as the hostname, as this will conflict with the email in your actual domain.com hosting account (with regards to how system accounts get their emails).

To change your hostname:

1. Go to:

   Admin Level -> Admin Settings -> Server's Hostname

   set it there, and allow 1 minute for DA to restart.
   
   
2. DA 1.52.2+ No longer requires this step due to functionality change, DA will rename the hostname zone for you:
   https://www.directadmin.com/features.php?id=2086
   

   ---

   1.52.1 and older
   The hostname must resolve, so go to:

   Admin Level -> DNS Administration -> Add Zone

   and create an entire new zone:

   Domain Name: server.domain.com
   IP Address: 1.2.3.4 (your server IP)
   ns1: ns1.domain.com
   ns2: ns2.domain.com

   where server.domain.com is your new hostname, the server IP address will usually be your license/main IP, and the ns1/ns2 values can be whatever your domain.com uses.  Leave the "Create Reverse IP Lookup" checkbox disabled/unchecked.
   The reason we add a new zone for the hostname is to ensure that
   - it resolves
   - it has it's own MX record, so email from the hostname are valid. Without the MX records, many of your emails (eg: from the php/apache "mail()" function) may be rejected.