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Debugging🔎

Login Woes🔎

Tracking down issues in /var/log/secure🔎

Repeated messages saying System Error with code 4: 

pam_sss(sshd:auth): received for user <user>: 4 (System error)
error: PAM: System error for <user> from <host>
may artificially inflate a user's failed login tally. Typically is a byproduct of a system issue. An sss_reset + tally reset helps.

From October 6, 2025:

Pam system error 4 is generally caused by one of the AD servers used for authentication being hosed, and linux’s sssd doesn’t see that in many cases, and continues to attempts against that same server.Â