The IP 23.234.31.88 has just been banned by Fail2Ban after 19 attempts against SSH. Latest lines containing IP:23.234.31.88 in /var/log/syslog/sshd.log Aug 7 00:50:15 ftlogin2 sshd[31817]: error: PAM: User not known to the underlying authentication module for illegal user admin from 23.234.31.88 Aug 7 00:50:15 ftlogin2 sshd[31817]: Failed keyboard-interactive/pam for invalid user admin from 23.234.31.88 port 56016 ssh2 Aug 7 00:50:25 ftlogin2 sshd[32111]: Invalid user admin from 23.234.31.88 Aug 7 00:50:25 ftlogin2 sshd[32114]: Postponed keyboard-interactive for invalid user admin from 23.234.31.88 port 56171 ssh2 Aug 7 00:50:26 ftlogin2 sshd[32111]: error: PAM: User not known to the underlying authentication module for illegal user admin from 23.234.31.88 Aug 7 00:50:26 ftlogin2 sshd[32111]: Failed keyboard-interactive/pam for invalid user admin from 23.234.31.88 port 56171 ssh2 Aug 7 00:50:26 ftlogin2 sshd[32114]: Postponed keyboard-interactive for invalid user admin from 23.234.31.88 port 56171 ssh2 Aug 7 00:50:28 ftlogin2 sshd[32111]: error: PAM: User not known to the underlying authentication module for illegal user admin from 23.234.31.88 Aug 7 00:50:28 ftlogin2 sshd[32111]: Failed keyboard-interactive/pam for invalid user admin from 23.234.31.88 port 56171 ssh2 Aug 7 00:50:28 ftlogin2 sshd[32114]: Postponed keyboard-interactive for invalid user admin from 23.234.31.88 port 56171 ssh2 - Fail2ban on