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Subject: Re: Hi. /31 on ethernet links
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> > A /31 subnet is only defined for point-to-point network links, per:
> >
> >   http://www.rfc-editor.org/rfc/rfc3021.txt
> >
> > Ordinary ethernet links have BROADCAST flag set instead of POINTOPOINT.
> >
> > Regards,
> Well how do I set the POINTOPOINT flag and remove the BROADCAST-flag on 
> ethernet links? Or are you implying that it does not belong on ethernet 
> links :)
> Cause Cisco and Linux support /31 (ptp's) on ordinary ethernet links.

No, Cisco does not *support* it. They make it available, which is a
completely different story.

We have asked Cisco repeatedly, through official channels, whether
they *support* /31 on Ethernet links. The answer is always that it
*may* work, use at your own peril.

Steinar Haug, Nethelp consulting, sthaug@nethelp.no