Re: Linux IPv6 DAD not full conform to RFC 4862 ?

On Wed, Jan 09, 2008 at 04:09:57PM -0500, Vlad Yasevich wrote:

Neil Horman wrote:

quoted

On Thu, Jan 10, 2008 at 01:38:57AM +0900, YOSHIFUJI Hideaki / 吉藤英明 wrote:

quoted

In article [ref] (at Wed, 9 Jan 2008 16:36:56 +0100), Karsten Keil [off-list ref] says:

quoted

So I think we should disable the interface now, if DAD fails on a
hardware based LLA.

I don't want to do this, at least, unconditionally.

Options (not exclusive):

- we could have "dad_reaction" interface variable and
 > 1: disable interface
 = 1: disable IPv6
 < 0: ignore (as we do now)

I like the flexibility of this solution, but given that the only part of the RFC
that we're missing on at the moment is that we SHOULD disable the interface on
DAD failure for a link-local address, I would think this scheme would be good:

  < 0 : ignore, and del address from interface (current behavior)   = 0 : 
disable interface for dad failure for a link-local address   > 0 : disable 
interface for dad failure for any address 
Regards
Neil
 

Just a friendly reminder that such a scheme should only be
applied to autoconfigured addresses.  A manually configured
duplicated address should not bring down the whole interface.

I agree, but I think that case would be covered by the default option above
(sysctl < 0).

Neil

-vlad