Hi,
There's a minor mistake in the Proxmox VE Wiki entry for Fail2ban.
This:
[proxmox]
enabled = true
port = https,http,8006
filter = proxmox
logpath = /var/log/daemon.log
maxretry = 3
bantime = 3600 # 1 hour
Should be:
[proxmox]
enabled = true
port = https,http,8006
filter = proxmox...