From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephen Hemminger <shemminger@vyatta.com>
Subject: Re: iproute2: adding /128 address to sit interface borks
Date: Fri, 10 Jul 2009 08:27:31 -0700
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Cc: Stephen Hemminger <stephen.hemminger@vyatta.com>,
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To: Jan Engelhardt <jengelh@medozas.de>
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On Fri, 10 Jul 2009 14:05:01 +0200 (CEST)
Jan Engelhardt <jengelh@medozas.de> wrote:

> Hi,
> 
> 
> it's impossible to do this, and the error message does not say why 
> that is so. No word in dmesg either.
> 
> 
> # ip a a fc00::49/128 peer fc00::7 dev sit7
> RTNETLINK answers: Invalid argument

You will need to walk through the path in the kernel.
In worst case, it means adding kernel printk's.

Then if you want to be nice, make a patch to ipaddr.c in iproute
utilities so command line can find the error before passing to
kernel and give a nice error :-)

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