dhcpcd-discuss

On Thu, Apr 25, 2019 at 02:33:34PM +0100, Roy Marples wrote:
> On 25/04/2019 14:18, Matt Horan wrote:
> > On Thu, Apr 25, 2019 at 02:06:46PM +0100, Roy Marples wrote:
> >> Well, dhcpcd is meant to handle everything.
> >> But if you want to continue using slaacd or something else that causes a
> >> PHY reset (which can trigger carrier loss) you still can!
> >>
> >> Send dhcpcd right to the background with the -b flag OR start it in
> >> master mode (ie don't specify an interface on the command line) and use
> >> the allowinterfaces directive instead to limit the interfaces dhcpcd uses.
> > 
> > Interesting. I am using the second option. The rc.d script starts dhcpcd
> > with -Mq and no interface is specified. I snipped the allowinterfaces
> > from my dhcpcd.conf, but that's in there too.
> > 
> > Here was the non-working dhcpcd.conf in its entirety:
> > 
> > option rapid_commit
> > 
> > allowinterfaces em0 em1
> > ipv6only
> > 
> > nohook resolv.conf
> > 
> > noipv6rs
> > interface em0
> >      ipv6rs
> >      ia_pd 0 em1/0
> > 
> > So perhaps something else is going wrong?
> 
> Hmmm, well in this case, dhcpcd should still continue fine and recover 
> from carrier loss.
> 
> Saying that, there were a few fixes to link detection between the dhcpcd 
> versions you mentioned, but to be fair I only tested this on NetBSD. 
> There's no reason why they are not applicable to the other BSD's, but I 
> cannot easily test that on my OpenBSD vm right now.
> 
> Does dhcpcd recover from carrier loss?

It doesn't seem so. After the first reboot I waited over a minute and
dhcpcd never got a lease. When I restarted dhcpcd it got a lease
immediately.

I do see that dhcpcd forks to the background, so it should still be
running, but seems to not detect that carrier has returned. IPv4 works
fine during the entire process, so I believe the interface is still up.

> Does OpenBSD announce interface down/up via route monitor correctly?

I'm not sure. Since this only happens on boot I'll have to wire
something up to capture this when it happens. I haven't been able to
reproduce after boot.

Thanks,

-- 
Matt Horan matt@xxxxxxxxxxxxx https://matthoran.com/