Fail2ban

Had issue with ssh bruteforce that's make my on-premise server (computer) being uncompromised then caused hang. We can leverage this like service to like ban, so prevent next access being process again and again even tho it's failed.

Debian 12

My on-premise server it's ran debian 12 bookworm. Here is some step I do.

sudo apt install fail2ban

sudo systemctl restart fail2ban
sudo systemctl enable fail2ban

Fail2ban UI

Look nice if we have or can able doing config with nice UI or through web browser. Then here is what I found swissmakers/fail2ban-ui. I don't need to like following what's common tutorial I have seen that's need to local copied configuration fail2ban had. I just copied the docker-compose.yml then map the port and ready to go. By default 'jail' it's configured for sshd.

'allowipv6' not defined in 'Definition'

Fail2ban it's not working or start on Debian 12. One of the err it's looks above the title. We can leverage this to fix it.

echo "sshd_backend = systemd" >> /etc/fail2ban/paths-debian.conf
systemctl restart fail2ban