OpenSSH

OpenSSH (Open Secure Shell) is a set of free software computer programs providing encrypted communication sessions over a computer network using the SSH protocol. It was created as an open alternative to the proprietary Secure Shell software. The project is led by Theo de Raadt from Calgary, Alberta in Canada.

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OpenSSH has been supported by fail2ban for a long time. Nothing special to write here.

Log IP Addresses

In your OpenSSH config (frequently /etc/ssh/sshd_config), include the line

UseDNS no