https://pmg.proxmox.com/mediawiki/index.php?action=history&feed=atom&title=Change_FQDNChange FQDN - Revision history2026-04-15T23:57:40ZRevision history for this page on the wikiMediaWiki 1.43.8https://pmg.proxmox.com/mediawiki/index.php?title=Change_FQDN&diff=44&oldid=prevMartin: page created2020-06-03T11:19:46Z<p>page created</p>
<p><b>New page</b></p><div>== Introduction ==<br />
<br />
Changing the fully qualified domain name (FQDN) or IP address of a Proxmox Mail Gateway installation is basically done like on any other GNU/Linux system.<br />
However, there are a few config files on which Proxmox Mail Gateway relies to get its configuration right.<br />
<br />
In most situations, you will need to make changes to your domain records to reflect the change of hostname and/or IP address since email delivery relies on correct DNS records.<br />
<br />
This short article will walk you through all the necessary places in which you might need to adapt the configuration.<br />
<br />
For the remainder we assume that:<br />
* we want to change the FQDN of our installation to <code>pmgchanged.proxmox.com</code> <br />
* we want to change the IP address and network to <code>192.0.2.72/24</code><br />
* the Gateway in our network is <code>192.0.2.1</code><br />
* the DNS server in our network is <code>192.0.2.53</code><br />
<br />
== Adapting the FQDN on the Proxmox Mail Gateway ==<br />
This needs to happen in 3 places:<br />
* <code>/etc/hostname</code> - the short hostname (<code>pmgchanged</code>, the part before the first <code>.</code>,) needs to be entered there.<br />
* <code>/etc/hosts</code> - there needs to be an entry with the main IP pointing to the short hostname and FQDN:<br />
<nowiki><br />
127.0.0.1 localhost.localdomain localhost<br />
192.0.2.72 pmgchanged.proxmox.com pmgchanged<br />
# leave remaining /etc/hosts untouched<br />
</nowiki><br />
<br />
* <code>/etc/resolv.conf</code> - needs to contain the domain name part as <code>search</code> - This can also be accomplished in the GUI (on the main Configuration Menu entry):<br />
<nowiki><br />
search proxmox.com<br />
nameserver 192.0.2.53<br />
</nowiki><br />
<br />
== Changing the IP configuration ==<br />
<br />
Adapt the <code>/etc/network/interfaces</code> file with the new IP<br />
<br />
<nowiki><br />
# comments<br />
auto lo<br />
iface lo inet loopback<br />
<br />
auto ens18<br />
iface ens18 inet static<br />
address 192.0.2.72/20<br />
gateway 192.0.2.1<br />
</nowiki><br />
== Consideration for clustered setups ==<br />
If you run a Proxmox Mail Gateway cluster, you will need to adapt <code>/etc/pmg/cluster.conf</code> with the changed IP addresses and hostnames and make sure that passwordless SSH authentication is still working between the nodes in the cluster.<br />
<br />
Additionally check all other nodes' <code>/etc/hosts</code> files to make sure that the old IP address and FQDN are replaced there as well.<br />
<br />
== Updating the IP and or FQDN on all relevant internal systems ==<br />
Change the internal systems which use the Proxmox Mail Gateway to the new IP or FQDN. This can be the mailserver which relays mails via the Proxmox Mail Gateway.<br />
<br />
== Changing all relevant DNS records ==<br />
Email relies on DNS records for its operation.<br />
* If you change the FQDN of your Proxmox Mail Gateway installation, make sure to update the MX records of all domains for which it relays email to the new FQDN.<br />
* Add or Update the A record of the FQDN to point to the current IP address of your Proxmox Mail Gateway<br />
* Update the reverse Pointer (PTR record) of the IP address to point to the new FQDN of your Proxmox Mail Gateway</div>Martin