Blocking A Class of Ips w/ Iptables

kemplej · 09-02-2004, 08:32 AM

I want to block a group of ips on my email server using iptables. Would the best way be to block say 192.168.1.0?

Capt_Caveman · 09-02-2004, 08:53 AM

What range do you want to block:
192.168.1.0 - ?

kemplej · 09-02-2004, 04:25 PM

192.168.1.* was just an example. My email servers just seem to get slammed by virii senders daily from the same ISP and I was just hopeing to block them out since they seem to be on a dialup modem.

Justyn

Capt_Caveman · 09-02-2004, 09:03 PM

The specific IP didn't matter, I was just trying to get an idea of how big a block you want to drop traffic from. Anyway, the general rule for blocking traffic:

For a single host (192.168.2.1):
iptables -I INPUT -s 192.168.2.1 -j DROP

For a range (192.168.2.0 - 192.168.2.255):
iptables -I INPUT -s 192.168.2.1/24 -j DROP

For a range (192.168.0.0 - 192.168.255.255):
iptables -I INPUT -s 192.168.0.0/16 -j DROP

kemplej · 09-03-2004, 11:02 AM

Cool thank you