Re: [2.4 PATCH] bugfix: ARP respond on all devices

From: Stephan von Krawczynski (skraw_at_ithnet.com)
Date: 08/20/03

  • Next message: Jeff Garzik: "Re: IDE wierdness" 
    Date:	Wed, 20 Aug 2003 17:41:33 +0200
To: "David S. Miller" <davem@redhat.com>

    On Tue, 19 Aug 2003 12:28:47 -0700
    "David S. Miller" <davem@redhat.com> wrote:

    > On 19 Aug 2003 21:32:35 +0200
    > Andi Kleen <ak@colin2.muc.de> wrote:
    >
    > > What happens on outgoing active ARPs is a different thing. Reasonable
    > > choices would be either the prefered source address of the route or
    > > the local interface's address. I must admit I don't have a strong
    > > opinion on what the better behaviour of those is, but neither of them would
    > > seem particularly wrong to me.
    >
    > Andi, we take the source address from the packet we are
    > trying to send out that interface.
    >
    > Just as it is going to be legal to send out a packet from
    > that interface using that source address, it is legal to
    > send out an ARP request from that interface using that source
    > address.

    Aehm, sorry but the logic is bogus. A routed packet will be sent out this
    interface with a foreign IP as source, too. Though nobody will want to send an
    arp request with a foreign ip as source.
    But you say here: Just as I can send out a packet with IP X from that interface
    I can send out ARP request with same source.
    Obviously you don't want that.
    So you cannot step from A to B in your logical chain here.

    Again. I'd like to stress I don't want to insult you or anything. The simple
    thing is this: there are a lot setups out there that could benefit from your
    tolerance in this issue. Can't we simply take the issue to the point: "you are
    right, but you show tolerance for boxes that are not completely wrong" ?
    I mean the world is full of people that are right and intolerant, so that in
    fact doesn't really make them special ...

    Please let us keep in mind that joe-average-user cannot handle complex setups
    with arpfilter, arp_filter or anything the like. But he can right away enter
    IT-superstore XYZ and buy a brand new router box for 20 bucks. If he is unlucky
    (and you stay intolerant) he will for sure _not_ blame this box but his desktop
    linux if things don't work out as expected.
    I think we should at least make a minimum effort to keep things simple (and
    explainable to joe-average-user), even if the background is complex.
    Everywhere we have a solution for a problem that is overly complex, we will
    fail to gain a broad market share, because there may very likely be easier
    solutions under <name-some-os> _and_ we attract support problems for all
    distributors.

    Regards,
    Stephan
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  • Next message: Jeff Garzik: "Re: IDE wierdness"

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