[fw-wiz] iptables firewall with multiple external interfaces routing probl em

From: Jeff Adam (jadam_at_seark.edu)
Date: 07/09/03

  • Next message: franco segna: "Re: [fw-wiz] linux firewall" 
    To: "'firewall-wizards@honor.icsalabs.com'" <firewall-wizards@honor.icsalabs.com>
Date: Wed, 9 Jul 2003 13:59:54 -0500

    The problem that I have run into is that only the first dhcp interface to
    activate will
    talk to the internet.

    I place my DMZ behind eth2 and my LAN behind eth1 and eth0 then forward port
    25
    on eth2 to my exchange server on my DMZ and 80 to my web server on my DMZ

    redhat 9 iptables fw
    eth0 external connected to cable dhcp reserve x.x.x.12
    eth1 external connected to cable dhcp reserve x.x.x.45
    eth2 external connected to cable dhcp reserve x.x.x.55
    eth3 internal connected to LAN 172.x.x.x
    eth4 internal connected to DMZ 192.x.x.x
    eth5 inactive not used

    The problem is that when the system boots only the LAN has internet
    connectivity
    behind eth0. I can deactivate eth0, eth1 and eth2, then activate only eth2,
    and only
    the DMZ has connectivity. The internet is able to connect back to the
    servers
    in my DMZ as planned. I then activate eth0 and eth1, and still only the DMZ
    has
    connectivity. I deactivate eth0-2 and only the interface that activates
    first appears
    to work. I am at a loss as to what I am missing.

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  • Next message: franco segna: "Re: [fw-wiz] linux firewall"

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