On Wed, Aug 25, 2010 at 09:52:16AM +0200, Nils Cant wrote: > Hey guys, > > not sure if this is a bug or a feature request. It's just something > we've noticed and are having problems with. > > We're using the qemu-kvm lenny-backports package on Debian 5.0.5. > > When doing a live migration from the virsh shell, the server in > question becomes unreachable because the ARP cache on our switches > still thinks the server is on another port. > > As soon as the server sends out some traffic, such as a ping, the > ARP cache get's updated as expected. If it does nothing, the server > remains unreachable until the ARP cache expires on the switches. (in > our case 4 hours) > > We would like to be able to do live migration for customer machines > on which we have no access, so we really need KVM to send out an ARP > announcement/gratuitous ARP when doing a live migration. > > Could anyone tell me if this is a bug in KVM, libvirt, or the debian > qemu-kvm package? (or if I'm doing something wrong? :-) ) > qemu sends gratuitous ARP after migration. Check forward delay setting on your bridge interface. It should be set to zero. > I've been tcpdumping the bridged network interfaces on the hosts > while doing the migrate, and couldn't see any ARP broadcasts. > > Debian 5.0.5 > Kernel: 2.6.32-bpo.3-amd64 > qemu-kvm 0.12.4+dfsg-1~bpo50+2 > libvirt0 0.7.6-1~bpo50+1 > > migrate --live testserver qemu+ssh://192.168.1.3/system > > Thanks in advance, > > Nils > -- > To unsubscribe from this list: send the line "unsubscribe kvm" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Gleb. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
