Re: [ovirt-users] R: R: R: R: PXE boot of a VM on vdsm don't read DHCP offer
On Fri, Jul 03, 2015 at 04:32:50PM +0200, NUNIN Roberto wrote:
Thanks for answering. My considerations below.
BR,
ROberto
> -----Messaggio originale-----
> Da: Dan Kenigsberg [mailto:danken@redhat.com]
> Inviato: venerdì 3 luglio 2015 12:31
> A: NUNIN Roberto
> Cc: users(a)ovirt.org; ibarkan(a)redhat.com
> Oggetto: Re: R: R: [ovirt-users] R: PXE boot of a VM on vdsm don't read
> DHCP offer
>
> On Fri, Jul 03, 2015 at 10:51:52AM +0200, NUNIN Roberto wrote:
> > Hi Dan, guys
> >
> > Sorry for very late follow-up, but we had a lot of other topics to fix just
> before to go back on this one.
> >
> > We have tried another approach just to check if the kernel of the vdsm iso
> image used to install the host could create the problem I've reported to the
> list.
> >
> > Now we have reinstalled the same hardware with latest CentOS 7.1, fully
> updated.
> > Installed vdsm, then joined the oVirt cluster.
> >
> > Well, we are observing the same behavior as before.
> > No DHCP offer is reaching the booting VM, and:
> >
> > brctl showmacs <bridge_if> show us the booting vm mac-address
> > tcpdump -I <bridge_if> show us the dhcp offer coming from dhcp server.
>
> The offer should be replicated to the tap device (vnetXXX). I assume
> that it does not?
The DHCP offer package coming from DHCP server flows thru the bond0
device (tagged), the VLAN device (tagged) and the bridge interface
(not anymore tagged, correct), so it seems that the path back is
complete, considering that brctl showmacs shows the vm mac and If we
put a static IP into the vm nic, it works correctly.
Let's try to trace the offer for one more link. If it does not get to
the tap device vnetXXX - it is clearly a host-side issue. Maybe a bridge
module bug. If you spot the offer on the tap, the it becomes more likely
that the issue is in qemu or elsewere in the virt stack.
I would appreciate your assistence!
>
> >
> > We have also tried to remove ANY firewall rule.
> >
> > It isn't a PXE issue (gPXE 0.9.7) but only a DHCP process issue. Infact, if
we
> install a vm manually and assign a static IP, it works fine.
> > If we switch to dhcp, the vm don't get the dynamic one.
> > In this case, tcpdump on vm shows only the DHCP discovery, not the DHCP
> offer.
> >
> > Any further suggestion/hint ?
We have mode 4, but already checked active/backup, mode 2, without changes.
Thanks, so it's not that bonding issue.
Regards,
Dan.