Re: -i interface filter not working for firewall

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victor oliveira wrote:


On 12/3/06, *Martijn Lievaart* <m@xxxxxxx <mailto:m@xxxxxxx>> wrote:

    victor oliveira wrote:

    > My problem is the following: I am able to connect from my machine to
    > the firewall using both eth2 and eth3. However, note that the INPUT
    > default is DROP, and the only rule on the INPUT SHOULD be filtering
    > and only allowing connections to the eth2 and not the eth3
    > interface...


    You rules are a bit messy, but it should probably work. Are you
    sure you
    connect through eth3? You do say it is from the same machine, if
    you are
    connected to eth2 and address the ip addres of eth3, you still
    come in
    through eth2.

eth2 and eth3 are both connected to the same switch, and are not virtual. Each with a different IP. eth2 has the IP 10.10.1.8 <http://10.10.1.8> and eth3 has the ip 10.10.1.9 <http://10.10.1.9>. I´m using for testing a putty application from another machine, also connected to the same switch.
I know it should be working but it is not.
Furthermore, I tested the mangle rules for multiple tables and it only works without the -i option. My "solution" was to change to different subdomains and just not use the -i restriction...
any thoughts ?


[ Please don't toppost]

Aha, but linux answers arp requests on any interface. So in this setup, an arp request for the address of eth3 can very well be answered by eth2. In fact it probably was, given your results. Try to turn of proxy_arp on the firewall or disconnect eth2 for the test. You'll probably see very different results then.

HTH
M4




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