Update Hostname and PTR

Hostnames and PTR (Pointer) records are essential components of the Domain Name System (DNS). A hostname is a label assigned to a device connected to the internet, used to identify it within a network. It typically takes the form of a human-readable name followed by a domain name, such as "server.example.com." Hostnames provide an easy way to reference and access network resources.

On the other hand, PTR records are a type of DNS record that maps an IP address to a hostname. They are commonly used for reverse DNS lookups, allowing you to determine the hostname associated with a given IP address. PTR records play a crucial role in various internet protocols and security measures, including email delivery, spam filtering, and network troubleshooting.

Hostnames and PTRs can only be updated for VPS or dedicated hosting, as these changes do require root access.  It's important that the chosen FQDN used for the hostname is not used for other purposes, like displaying sites, or used for other services such as mail, FTP, cPanel, WHM, etc.  The hostname should be 60 or fewer lowercase, standard Latin characters (eg. a, b, c and not á, д, 某, or any other non-Latin characters).

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PTR/Hostname Update

IMPORTANT: This solution will require root access. If this needs to be obtained, follow the guide on requesting root access.
CAUTION: Some of these steps require access to our network.  As such, you will need to reach out to our Technical Support team to update the PTR, as well as to make the hostname change permanent on VPS hosting.
 

1. Choose a custom hostname to use
   EXAMPLE: "server.domain.com" or "vps.domain.com".
   CAUTION: The hostname should never be used for other tasks on the server, such as mail, FTP, WHM, etc.
2. Set the hostname
   1. SSH into the server

   2. Run the following

      /usr/local/cpanel/bin/set_hostname [hostname]

      REPLACE: [hostname] with the hostname chosen.
      CAUTION: On a VPS, this will only update the hostname until the next reboot.

3. Confirm a DNS A record exists with the name of the selected hostname that points to the primary IP of the server
   TIP: You can check the current PTR Value with host [IP] or dig -x [IP address]. You can check the current hostname by running hostname on the server.
   1. Search the hostname using a DNS-checking tool such as dnschecker.org
      EXAMPLE: In this example, the A record for the hostname does not exist and will need to be created.
      
   2. If one does not exist, create an A record for the hostname
      TIP: If the domain uses third-party nameservers, create the A record with the third party.
4. Reset the service SSLs
   NOTE:  Resetting the service SSLs will assist with security warnings from cPanel and WHM after setting the new hostname.
5. Reach out to our Technical Support team to update the PTR record
   IMPORTANT: On a VPS, request to have the hostname updated on the node as well.  Otherwise, the hostname will revert if the VPS is rebooted.
   NOTE: Once updated, DNS propagation can take 4 to 24 hours.