How to Block all ports with Fail2ban

This was difficult to find so I’m noting it here for future reference. To block all ports with fail2ban, change the jail file’s port value to “0:65535”

For example, here’s my SSH Jail file:

[ssh-iptables]
enabled = true
filter = sshd
action = iptables[name=SSH, port=”0:65535″, protocol=tcp]
sendmail-whois[name=SSH, dest=nospam@example.com, sender=nospam@example.com, sendername=”Fail2Ban”]
logpath = /var/log/secure
maxretry = 3