email ports forwarding w/ existing local email server.
I have to forward email ports from local net to the whole world. At
the same time I have a local email server that functions too. -
Therefore I have I divide the requests between those coming to the
local one and those that go to the outer one.
Having said that I have:
world's net - 18.104.22.168
local net - 192.168.0.0/24
iptables firewall, w/ running email server - 192.168.0.1
eth0 - the world's net
eth1 the local one.
Here is how I try to accomplish this:
/sbin/iptables -A FORWARD -i eth1 -s 192.168.0.0/24 -p tcp -m multiport
--dports 25,110 -j ACCEPT
/sbin/iptables -t nat -A PREROUTING -s
192.168.0.0/24 -p tcp --dport 25000 -j DNAT --to-destination
/sbin/iptables -t nat -A POSTROUTING -i eth1 -s
192.168.0.0/24 -j SNAT --to-source=22.214.171.124
My questions are:
1. Is it all correct/safe in any way, or needs additional correction?
2. _______ - what should I use here in case I do not want to limit the
access to a single email server?
Thank You for Your time.