ipt_ROUTE loopback

From: Jon Masters (jonmasters_at_gmail.com)
Date: 11/17/05

  • Next message: Jon Masters: "Re: OSDL Patent Commons for Linux" 
    Date:	Thu, 17 Nov 2005 03:01:46 +0000
To: Linux Kernel <linux-kernel@vger.kernel.org>

    Folks,

    I'm trying to find an easy way to have a Linux box completely ignore
    the local routing table and have traffic destined for one interface go
    out of a loopback cable and back into the other rather than traversing
    the local routing within the host, viz:

    eth0
    x.x.x.x
       |
       | <--- loopback cable
       |
    eth1
    y.y.y.y

    This is completely against normal practice, but useful for test. I've
    so far tried playing around with iproute2 and have this evening built
    up ipt_ROUTE, which seems more promising. I can get traffic forced out
    of the "correct" interface and bypass the local routing table, but it
    always has the destination MAC of the first interface when it reaches
    the second.

    So, I can bodge the destination MAC (I'm still deciding how to do that
    - maybe I'll take apart ipt_ROUTE and have it do MAC rewriting too)
    but I'm curious as to whether there's a "right" way to do this that
    I've so far missed? I've considered using the briding code in some
    weird kind of transparent-yet-not-really bridge setup, but I don't
    really want to do that.

    Any suggestions? This seems like something others must have also
    wanted to do. I'm happy to break things in doing it, but I'm hopeful
    for a "you missed this page...".

    Jon.
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  • Next message: Jon Masters: "Re: OSDL Patent Commons for Linux"

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