Originally Posted by manarak
if you install a vserver: these usually don't allow access to IPTABLES, since they are built into the kernel that is common to all vservers on the host.
So your fail2ban is going to be ineffective in the default config.
solution: use hosts.deny instead.
to do this:
banaction = iptables-multiport
banaction = hostsdeny
save and restart fail2ban
I realized later that hosts.deny is not a good solution. see here why: