Securing SSH access on a DirectAdmin server is simple when using CSF (ConfigServer Security & Firewall).
To do so, just follow these two steps:
-
Add the IP addresses from which you want to allow SSH access to the whitelist file (
csf.allow
) -
Remove the SSH port from the
TCP_IN
list in thecsf.conf
configuration file
This effectively blocks all SSH access except from the IPs you’ve explicitly allowed.