Subject: Re: [IPV6] addrconf: Fix IPv6 on tuntap tunnels

From: Vlad Yasevich <[email-masked]>
Date: Fri, 15 Jun 2007 16:42:22 -0400

Oliver Hartkopp wrote:
> Hallo David, hello Herbert,
> 
> indeed i have some concerns about reverting the patch as i do not see
> that the MTU is the right thing to distinguish whether a netdevice is
> capable to have IPv4/IPv6. E.g. is decnet able to run IPv6?
> 
> IMHO the autoconf (in any case) should only handle netdevices that are
> capable to be auto configured (e.g. with IPv6).
> 
> So the question looks like:
> "Is this device capable to be auto configured with IPv6?"
> and not
> "Is the devices MTU >= IPV6_MIN_MTU ?"

No, the questions should really be:

1.  Is IPV6 supported over this media type.
	yes: got to 2
	no:  stop

2.  Is the device MTU >= IPV6_MIN_MTU
	yes: continue
	no:  stop

Autoconfiguration is a layer on top of IPv6.  Whether it's enabled
or not should not dictate whether IPv6 addressed may be configured or not.

-vlad