Subject: Re: [vserver] Need advice on which path to take for IPv6 support
From: Herbert Poetzl <herbert@13thfloor.at>
Date: Thu, 7 Jan 2010 19:29:14 +0100

On Thu, Jan 07, 2010 at 01:04:39PM -0500, Paul Kyzivat wrote:
> Hello - this is my first time posting here.

> The project I am working on is currently using:
> - kernel 2.6.22.10
> - patch-2.6.22.10-vs2.2.0.5.diff

> That is working for us, but now we want to have support for IPv6 in the 
> guests. I am trying to decide the most practical way to get there.

> At the moment, the most straightforward path seems to be:
> - kernel 2.6.22.19
> - patch-2.6.22.19-vs2.3.0.34.diff

> We are seriously considering that. But some of our people are
> concerned that we might have migration issues to deal with, or at
> least extra testing if we go that way, and are desirous of a more
> minimalist change.

> (We had previously been using patch-2.6.14.3-vs2.01.diff. When        
> we migrated to patch-2.6.22.10-vs2.2.0.5.diff some of our guests      
> encountered incompatibilities that we didn't discover until after 
> the fact.                                                                 

just curious, what were the incompatibilities you discovered?

> That is making people gun shy. There is also some concern over 
> switching from a "stable" release to a "development" release.)

actually it is an experimental release :)

> So I've also been investigating the possibility of adding the IPv6 
> capabilities to the vserver version we have. I see that was done for 
> some vserver versions via additional patches from:
>   http://people.linux-vserver.org/~bonbons/ipv6/
> But there isn't such a patch for our kernel/vserver combination.

> I also note some discussion on your mailing list here that you 
> are getting ready to release a new *stable* vs release. 

we are on the verge to a devel release, which will be
the basis for further stabilization and testing which
should ultimately result in a new stable release, but
there are quite some things to do till then, and till
now the interest in helping with testing is quite low,
so it might take a while ...

> Depending on when that is to be available, maybe we should be
> considering that one too.

you might consider a recent 2.6.31/32 kernel and patch
as it will be the basis for that upcoming stable, and
simply switch to that stable version once it is available

> I have some questions whose answers should help decide among the 
> possibilities:

> - Is there a way to determine what user impacting changes there
>   are between the version we are on and some newer version, say
>   patch-2.6.22.19-vs2.3.0.34.diff?

that's not really 'newer' it is just a different branch,
same kernel/time ....

>   (I have looked at the change logs, but I can't easily extrapolate
>   how those changes would affect existing user code.)

most likely there are no effects at all

> - Would it make *any* sense to try porting one of the IPv6 patches
>   to vs2.2.0.5???

not really, but feel free to do so if you like :)

> - When do you expect to release the next stable version?

when it's ready ... feel free to speed that up by donations
or contributions (mostly time or resources)

> - What kernels with that next stable version support?

most likely 2.6.31+

> - How will this stable version differ from vs2.3.0.34?

it will be thoroughly tested, have full CFS integration
and no known bugs :)

HTH,
Herbert

> 	Thanks,
> 	Paul (Kyzivat)