Hi,
Here is my configuration :
OS : Red Hat Linux 9.0
eth0 : 1.1.1.1 (internal IP)
eth0 gateway : -none-
eth1 : 2.2.2.2 (external Live internet IP)
eth1 gateway : 2.2.2.3
I have setup squid for all internal clients to connect to the internet using IE (the same segment on eth0). I need to setup a connection that is accepted on eth0 for port 110 and port 25 and redirect it to internet IP 3.3.3.3 port 110 and 25.
I'am using this configuration for IPtables (entered on /rc.d/rc.local) :
echo 1 > /proc/sys/net/ipv4/ip_forw
ard
iptables -t nat -A POSTROUTING -o eth1 -j MASQUERADE
iptables -t nat -A PREROUTING -t nat -p tcp -d 1.1.1.1 --dport 25 -j DNAT --to 3.3.3.3:25
iptables -t nat -A PREROUTING -t nat -p tcp -d 1.1.1.1 --dport 110 -j DNAT --to 3.3.3.3:110
I don't want to use MASQUERADE because clients can bypass SQUID proxy server and use 1.1.1.1 instead as a Gateway. If I don't use MASQUERADE, it wont forward the connection to outside (internet).
I need help on making people browse the internet using SQUID, and access mail directly from the internet, in the same time blocking people from using 1.1.1.1 as their gateway. All using the same IP 1.1.1.1
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