Linux : Mail issues after renaming server hostname

By | July 26, 2020

If you changed the hostname/FQDN of a Linux server, you may end up with some issues, especially with mailing if some areas were forgotten with that change. Here is a quick procedure involving all the steps you should be looking for. (The following example is based on a Debian Linux system running Postfix MTA.)

1. Update the hostname file :


2. Update the hosts file :


3. Update the mailname file :


4. Update the Postfix file :


myhostname =
mydestination =

5. Update the DNS pointer record (PTR), if you had any : IN PTR your-new-hostname.domain.tld



6. Update the aliases file if you had any added entries with the previous FQDN


6.1. Rebuild the aliases database :