Re: PATCH: duplicate IP detection

Marc Merlin (marc_news@merlins.org)
Fri, 15 Oct 1999 15:59:58 -0700


On ven, oct 15, 1999 at 06:45:51 -0400, Wakko Warner wrote:
> > > Is there a userland program that can see if the IP is in use or not? Be
> > > nice to know if the IP is used before setting an IP on the nic.
> >
> > We discussed that last time, and I think it was Roger who proposed a patch
> > to ifconfig so that it would send an ARP request first and complain if the
> > IP you're trying to set is already used.
> >
> > We're left with the question as to whether ifconfig should by default
> > complain but put the IP anyway, or refuse to put the IP unless you give it
> > some --ignore-IP-conflict flag.
> > That approach is not incompatible with the kernel patch, and I believe that
> > both should be implemented.
>
> IMO long options like this are annoying. I used to not think so until I had
> to use a bunch of 15 char options on a commond once.

Note that I wrote "_some_ --ignore-IP-conflict flag".
It was just a quicker way to write "a forceip flag that would in essence
bring the interface up, even if we find out that the IP is already being
used by some other machine" :-)

I personally don't really care what the option is called anyway...

(For those who missed the original discussion, the point was that refusing
to bring the interface up by default would cause denial of service problems)

Marc

-- 
Microsoft is to software what McDonalds is to gourmet cooking
 
Home page: http://marc.merlins.org/ (friendly to non IE browsers)
Finger marc_f@merlins.org for PGP key and other contact information

- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/