June 2025
Beginner to intermediate
1180 pages
37h 48m
English
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26.4 Postfix Accounts
The following generally applies to Postfix: every regular user in /etc/passwd is also a mail user. No additional configuration is required for these users. Each of these Linux users can send and receive emails.
External mail clients such as Thunderbird must authenticate with Postfix or Dovecot. The regular Linux passwords are also used for this authentication. (This is a big difference compared to Samba; this file server maintains separate passwords for each Samba user.)
Mail Password as a Security Risk
As convenient as it is to have Linux and mail users running in parallel by default, it can also be risky.
Probably nobody would be so unwise as to use root as a regular email account (i.e., root@a-company.com) as this ...
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