Reserved and Invalid Usernames
Basic restrictions
OpenPanel
OpenPanel applies the following rules when you create or modify a OpenPanel username:
Usernames may only use lowercase letters (a–z) and digits (0–9).
- Usernames cannot contain less than 3 characters.
- Usernames cannot contain more than 20 characters.
OpenAdmin
OpenAdmin applies the following rules when you create or modify an admin username:
Usernames may only use lowercase letters (a–z) and digits (0–9).
- Usernames cannot contain less than 5 characters.
- Usernames cannot contain more than 30 characters.
Passwords may only use lowercase letters (a–z) and digits (0–9).
- Passwords cannot contain less than 5 characters.
- Passwords cannot contain more than 30 characters.
SSH
OpenAdmin applies the following rules when you modify an SSH password:
Passwords may only use lowercase letters (a–z) and digits (0–9).
- Passwords cannot contain less than 8 characters.
- Passwords cannot contain more than 20 characters.
MySQL / MariaDB
OpenPanel applies the following rules when you create databases and users:
Database names may only use lowercase letters (a–z) and digits (0–9).
- Database name cannot contain less than 1 character.
- Database name cannot contain more than 64 characters.
Database users may only use lowercase letters (a–z) and digits (0–9).
- Usernames cannot contain less than 1 characters.
- Usernames cannot contain more than 32 characters.
Database User's Passwords may only use lowercase letters (a–z), underscores (_) and digits (0–9).
- Passwords cannot contain less than 8 characters.
- Passwords cannot contain more than 32 characters.
FTP
OpenPanel applies the following rules when you create FTP sub-accounts:
FTP sub-users must end with dot (.) followed by the OpenPanel username - example: ftpuser.openpaneluser.
- Usernames cannot contain less than 3 characters.
- Usernames cannot contain more than 32 characters.
FTP User's Passwords must contain at least one uppercase letters (A-Z), lowercase letters (a–z), digits (0–9) and special symbols (!, ., ,, @, #, _, -).
- Passwords cannot contain less than 8 characters.
- Passwords cannot contain more than 32 characters.
Emails
OpenPanel applies the following rules when you create email accounts:
Email accounts may only use lowercase letters (a–z), dashes (-), underscores (_) and digits (0–9).
Email accounts must contain @ symbol followed by the domain name - example: account@example.net.
- Usernames cannot contain less than 1 character.
- Usernames cannot contain more than 32 characters.
Email accounts passwords can contain only uppercase letters (A-Z), lowercase letters (a–z), underscores (_) and digits (0–9).
- Passwords cannot contain less than 8 characters.
- Passwords cannot contain more than 32 characters.
Reserved usernames
OpenPanel reserves some usernames for the system’s use, and you cannot use them for OpenPanel accounts. This list of reserved usernames can grow over time, and new versions of OpenPanel may add to this list.
OpenPanel checks the following file to determine whether to reserve or restrict a username:
/etc/openpanel/openadmin/config/forbidden_usernames.txt
Currently reserved usernames:
- 1000
- admin
- apache
- apache2
- backup
- busybox
- cron
- docker
- elasticsearch
- exec
- filebrowser
- ftp
- httpd
- litespeed
- lsws
- mariadb
- memcached
- minecraft
- mssql
- mysql
- mysqld
- nginx
- openadmin
- openpanel
- openresty
- opensearch
- pgadmin
- php
- php-fpm-5.6
- php-fpm-7.0
- php-fpm-7.1
- php-fpm-7.2
- php-fpm-7.3
- php-fpm-7.4
- php-fpm-8.0
- php-fpm-8.1
- php-fpm-8.2
- php-fpm-8.3
- php-fpm-8.4
- phpmyadmin
- podman
- postgres
- reboot
- redis
- restart
- root
- shutdown
- test
- user_service
- varnish
- vsftpd
- www-data
To reserve a certain username, simply add it to the forbidden_usernames.txt file.