Only recommended for a fresh setup. I do not take any responsibility if you brick your config. Always make sure you have a recent backup of your config before tinkering with the config-file!
If you are using for example pfELK for analysing your logs from your pfSense firewall, you may want to rename your interfaces for less confusion.
You can do the editing of the config directly via the shell or by downloading a backup and editing the file and restoring. After the reboot you will have to reconfigure the interfaces.
Open the xml-file and pretty at the beginning of the file you will find somethin similar to:
<?xml version="1.0"?> <pfsense> <version>21.7</version> <lastchange></lastchange> <system> <optimization>normal</optimization>
<optimization> you can add
<earlyshellcmd>-lines. Right below
<system> you add something similar to:
<earlyshellcmd>/sbin/ifconfig vtnet0 name WAN; /sbin/ifconfig vtnet1 name LAN; /sbin/ifconfig vtnet2 name DMZ;</earlyshellcmd>
Now you only have to find the lines where your "old" interface names are in e.g.
<if>vtnet0</if> and replace the interface with the new name accordingly - in this case
<if>WAN</if>. Save the file (if you edited the file via the backup-option do a restore) and reboot your firewall. Later the interface-configuration wizard on the console will show up, set the interfaces as needed. That is all.