Re: Why no printk for duplicate IPs?

Joe Moore (Joe.Moore@sdrc.com)
Thu, 30 Sep 1999 10:22:12 -0400

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Maybe in reply to: Marc MERLIN: "Why no printk for duplicate IPs?"

owner-linux-kernel-digest@vger.rutgers.edu wrote:
>
> linux-kernel-digest Wednesday, 29 September 1999 Volume 01 : Number 4537
>
> From: Marc Merlin <marc_news@merlins.org>
> Date: Wed, 29 Sep 1999 15:21:01 -0700
> Subject: Re: Why no printk for duplicate IPs?
>
> On mer, sep 29, 1999 at 11:47:29 +0100, Alan Cox wrote:
> > > So, is it correct that for IPv4, linux won't report the fact that another
> > > machine is answering ARP requests for one of its IPs?
> > >
> > > If so why?
> >
> > ARP Replies are unicast
>
> good point.
>
> However, at least Solaris, Irix and 95/NT give you a warning when someone
> steals your IP (at runtime, not ifconfig time).
> I suppose they do an ARP request on their own IP after answering an ARP
> request themselves, and watch for an answer.
>
> Any reason we can't do that?

Would a userspace job that periodically ARPs for our own address and
logs a message if it gets a non-local response be sufficient?

Just an idea.

--Joe

-- IBM's vision is apparently to make IBM hardware "scream with Microsoft software" --The Register, http://www.theregister.co.uk/990927-000003.html

I have visions of screaming with (at and about) Microsoft software, too.

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Next message: Stephen C. Tweedie: "Re: pinning down user memory..."
Previous message: Uwe Solleder: "PROBLEM: Linux does not recognice more then 39000 Users"
Maybe in reply to: Marc MERLIN: "Why no printk for duplicate IPs?"