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Knowledge Base

What limits are set in Plesk for username/password?

 
dashlinuxmailospasswords

Question

What limits are there in Plesk for username/password?

Answer

Usernames and passwords in Plesk are case-sensitive.

Username and password length have the following limits:

  • Plesk user name length: from 1 to 255 symbols;
  • Plesk user password length: from 5 to 255 symbols;
  • System user name length: from 1 to 32 symbols for Linux, 1 to 20 symbols for Windows;
  • System user password length: from 5 to 255 symbols;
  • Mail address: up to 64 symbols (not counting '@' and domain part)

Character limitations are separate for different groups of users:

For Customers/Resellers:

  • The first character is limited to alphanumeric characters.
  • " " (Space) is prohibited.
  • System user names on the OS (Linux "root" and Windows "Administrator") are also prohibited.

For additional users (added in Users > User accounts menu):

  • The first character is limited to alphanumeric characters.
  • Characters from all languages ​​are allowed.
  • Special sentences other than (& @.'+ -) are prohibited.
  • System user names on the OS (Linux "root" and Windows "Administrator") are also prohibited.

Character limitations for system users are based on the target OS:

  • For Linux, only lowercase English letters, numbers,-(dash), and .(dot) are allowed. The first character is limited to letters.
  • For Windows, only English letters, numbers, -(dash), .(dot), _ (underscore) are allowed. The first character is limited to alphanumeric symbols.

Character restrictions for passwords:

  • The string is limited to the first 126 ASCII characters.

  • " " (Space), " " (quotation marks), "" "" (double quotation marks) are prohibited.

  • The password cannot include the user name.
    Example: User: qwerty Password: 1@qwerty2$

The system user password restrictions are the same as the target OS, although they differ depending on the distribution.

These limits are hard-coded, which means they cannot be changed in Plesk configuration. Additionally, system limits have a higher priority than limits configured in Plesk.

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