[options] logfile = /var/log/knockd.log [openSSH] sequence = 7000,8000,9000 seq_timeout = 5 command = /usr/sbin/iptables -A INPUT -s %IP% -p tcp --dport 22 -j ACCEPT tcpflags = syn [closeSSH] sequence = 9000,8000,7000 seq_timeout = 5 command = /usr/sbin/iptables -D INPUT -s %IP% -p tcp --dport 22 -j ACCEPT tcpflags = syn [openHTTPS] sequence = 12345,54321,24680,13579 seq_timeout = 5 command = /usr/local/sbin/knock_add -i -c INPUT -p tcp -d 443 -f %IP% tcpflags = syn