[ovirt-users] R: R: R: R: R: PXE boot of a VM on vdsm don't read DHCP offer

-----Messaggio originale----- Da: Dan Kenigsberg [mailto:danken@redhat.com] Inviato: lunedì 6 luglio 2015 10:02 A: NUNIN Roberto Cc: users(a)ovirt.org; ibarkan(a)redhat.com Oggetto: Re: R: R: R: [ovirt-users] 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.