On Tue, 2021-07-27 at 16:43 -0400, H wrote:
> > Running CentOS 7. I was under the impression - seemingly mistaken -
> > that by adding a rule to /etc/hosts.deny such as ALL: aaa.bbb.ccc.*
> > would ban all attempts from that network segment to connect to the
> > server, ie before fail2ban would (eventually) ban connection
> > attempts.
>
> This, however, does not seem correct and I could use a pointer to
> correct my misunderstanding. How is hosts.deny used and what have I
> missed?
hosts.deny is only used by specific programs that use TCP wrappers. It
is not a general "deny this host access".
Also note that fail2ban operates on individual hosts, not subnets.
>
> Is it necessary to run:
>
> iptables -I INPUT -s aaa.bbb.ccc.0/24 -j DROP
>
> to drop incoming connection attempts from that subnet?
>
If you use iptables yes, probably. Firewalld has a specific drop zone
that you can use:
firewall-cmd --zone=drop --add-source=aaa.bbb.ccc.0/24
(with suitable --permanent flag if you want it permanent).
P.
_______________________________________________
CentOS mailing list
CentOS@xxxxxxxxxx
https://lists.centos.org/mailman/listinfo/centos
