How to restrict the maximum simultaneous ssh logins from a specific user on AlmaLinux, CentOS

There should be pam_limits.conf module present in /etc/pam.d/system-auth. On older systems, this entry must also be in system-auth and password-auth files. grep limit /etc/pam.d/system-auth session required pam_limits.so Add maxlogins entry in /etc/security/limits.conf as follows: username hard maxlogins 'number of max logins' Enable PAM in /etc/ssh/sshd_config file as follows: UsePAM yes

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