The IP 123.30.242.51 has just been banned by Fail2Ban after 19 attempts against SSH. Latest lines containing IP:123.30.242.51 in /var/log/syslog/sshd.log Aug 11 07:16:05 ftlogin2 sshd[30160]: Failed keyboard-interactive/pam for invalid user admin from 123.30.242.51 port 52147 ssh2 Aug 11 07:16:15 ftlogin2 sshd[30167]: Address 123.30.242.51 maps to static.vdc.vn, but this does not map back to the address - POSSIBLE BREAK-IN ATTEMPT! Aug 11 07:16:15 ftlogin2 sshd[30167]: Invalid user admin from 123.30.242.51 Aug 11 07:16:16 ftlogin2 sshd[30170]: Postponed keyboard-interactive for invalid user admin from 123.30.242.51 port 52490 ssh2 Aug 11 07:16:17 ftlogin2 sshd[30167]: error: PAM: User not known to the underlying authentication module for illegal user admin from 123.30.242.51 Aug 11 07:16:17 ftlogin2 sshd[30167]: Failed keyboard-interactive/pam for invalid user admin from 123.30.242.51 port 52490 ssh2 Aug 11 07:16:17 ftlogin2 sshd[30170]: Postponed keyboard-interactive for invalid user admin from 123.30.242.51 port 52490 ssh2 Aug 11 07:16:18 ftlogin2 sshd[30167]: error: PAM: User not known to the underlying authentication module for illegal user admin from 123.30.242.51 Aug 11 07:16:18 ftlogin2 sshd[30167]: Failed keyboard-interactive/pam for invalid user admin from 123.30.242.51 port 52490 ssh2 Aug 11 07:16:19 ftlogin2 sshd[30170]: Postponed keyboard-interactive for invalid user admin from 123.30.242.51 port 52490 ssh2 - Fail2ban on