Question Warnings in mail log [SASL LOGIN authentication failed]

[andrecab93]

Server operating system version

Ubuntu 22.04.3 LTS

Plesk version and microupdate number

Version 18.0.58 Update #2

I check this information in the email logs several times:

2024-02-02 13:23:14	WARNING	postfix/smtpd [3512567]	warning: unknown[IPXXXX]: SASL LOGIN authentication failed: authentication failure
2024-02-02 13:23:14	WARNING	plesk_saslauthd [3512587]	failed mail authentication attempt for user '[email protected]' (password len=9)

2024-02-02 13:22:37	WARNING	postfix/smtpd [3512567]	warning: unknown[IPXXXX]: SASL LOGIN authentication failed: authentication failure
2024-02-02 13:22:37	WARNING	plesk_saslauthd [3512569]	failed mail authentication attempt for user 'glendali' (password len=9)

and so on, does anyone know how to solve it? I already have fail2ban activated but it's still there, is that normal?

 

[Peter Debik]

Yes, it is normal that servers get attacked all the time.