dhcpcd-discuss

On 2016-01-29 13:29, Nick Williams wrote:
> > On Jan 29, 2016, at 1:53 AM, Roy Marples <roy@xxxxxxxxxxxx> wrote:
> > > I need to think about this a bit more to be sure, but I don’t think 
> > > `service
> > > slaac` is related to dhcpcd at all. It’s appropriate at that spot in 
> > > the
> > > config, because it’s related to PD, but it’s actually a config 
> > > telling the
> > > DHCP //server// to enable SLAAC on those interfaces.
> >
> > DHCP server's don't care about SLAAC.
> > RA servers don't either.
> > SLAAC is strictly a client only thing.
>
> Yes, SLAAC is a client thing. However, my understanding is that, when
> the client needs an IPv6, it sends a solicitation request to the
> router, which, in the SLAAC case, responds “The current prefix is
> 2620:0:2d0:201::1/64, use SLAAC to figure it out yourself.”  Am I
> wrong?

You're correct.

> New question, about versions: I already noticed on here that twice
> recently you’ve asked someone using DHCPv6 to confirm that they’re on
> version 6.10.1. With that knowledge, and thinking there might be an
> important reason for that,

I always ask the version.
If they are not running the latest, I encourage them to upgrade and 
re-test because it could perform differently.
Could fix the issue, could cause another. I don't have the time to 
support any specific version, I just provide a rolling release via 
fossil and a release about once a month if I think it's stable enough, 
which it generally is.

> I looked at the versions currently
> available for standard Debian (the OS on which VyOS runs):
>
> - Squeeze has dhcpcd version 3.2.3-5
> - Wheezy has dhcpcd5 version 5.5.6-1 and dhcpcd 3.2.3-11
> - Jessie has dhcpcd5 version 6.0.5-2
> - Stretch has dhcpcd5 version 6.9.3-1
>
> It always disappoints me to see how far behind some distros are.
> Anyway, so none of them have 6.10.1. Jessie is the current stable, but
> seems to still be 2.5 years behind, and Stretch is Debian-next, and
> seems only to be a few months behind. VyOS is, unfortunately, still on
> //Squeeze//, but we’re actively working on getting it switched to
> Jessie.
>
> Still it doesn’t sound like Jessie is new enough, and even Stretch
> might not be. Is there a series of important bugs than have been fixed
> between versions 6.0.5 and 6.10.1? What’s the minimum version we need
> to use to not run into problems with DHCPv6? (I never have understand
> what the -n at the end of Debian package version names is, but I’m
> assuming it’s unimportant here, and that 6.0.5-2 is just 6.0.5?) Do
> you know of a trustworthy package repo that has dhcpcd version 6.10.1
> available for Jessie, or are we going to have to package it ourselves?

All code has bugs.
Once you accept that, you need to do, as VyOS maintainer, due diligence 
on each package to ensure it meets your needs and functions correctly.
dhcpcd is no exception here.
If you find a feature lacking or a bug blocking you then you need to 
correct it either by upgrading the package or patching it.

> Is there a series of important bugs than have been fixed
> between versions 6.0.5 and 6.10.1? What’s the minimum version we need
> to use to not run into problems with DHCPv6?

I'll pick that out :)
What is an important bug? Once you have an answer to that, realise that 
this importance only applies to you - others might have other issues 
they deem of a higher importance.
Let us also consider this - today I added a new feature that allows you 
to configure the suffix of each address added via Prefix Delegation 
(prior releases forced EUI64, then ::1).
Is this killer enough that you want to roll with a dhcpcd snapshot?

I cannot possibly answer this question :D
Which is why I always encourage users to try the latest release because 
there's a real possibility their issue has been fixed or at least 
improved.
I can at least tell you this - if hotplugging of interfaces is something 
you do, don't use dhcpcd-6.10.0, use an older or newer release ;)

Thanks

Roy