[Shorewall-users] Routing or Masq between multiple internal networks

Tom Eastep teastep@shorewall.net
Thu, 11 Apr 2002 18:57:39 -0700 (Pacific Daylight Time)

On Thu, 11 Apr 2002, gilsonsoares@gilsonsoares.com wrote:

> I have a quad ethernet in a RH72 system.
> eth0 is the net
> eth1,2,3 are internal networks
> I was trying to connect pop3 from eth1 to eth3.
> Even with policies and rules permitting free traffic
> between then I wasn't able to connect.
> To solve I JUST insert in MASQ file a line: "eth1 eth3".
> Why I need to insert a masq from eth1 to eth3 to be
> able communicate from one to another ?
> Why net.ipv4.ip_forward=1, routing table, policies and
> rules weren't enough to permit the traffic ?

Probably because the routing tables on the systems connected to eth1 and
eth3 aren't correct. Have you set their default gateway to the IP address
of the firewall interface that they are connected to?

Tom Eastep    \ Shorewall - iptables made easy
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