Re: Is it possible to live migrate guest OS'es between different versions of kvm/qemu-kvm?
Hey Juan, do you also think future releases of kvm will have support for live migration from older versions? We're quite keen on knowing this, as we need to make a decision on what to build our stuff on. Being able to transparently move virtual servers onto a host running a newer version is definitely a feature we need... Thanks in advance, Nils On 09/05/2010 10:39 AM, Avi Kivity wrote: On 09/03/2010 02:35 PM, Nils Cant wrote: First, don't trim the cc list. It's evil. Is this something we can depend on for future releases then? If we decide now to build a virtual hosting farm on 0.12, will we be able to use live migration in the future if we decide we want to upgrade to 0.13 or later? I believe so. Juan, can you confirm? -- To unsubscribe from this list: send the line unsubscribe kvm in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Is it possible to live migrate guest OS'es between different versions of kvm/qemu-kvm?
Is this something we can depend on for future releases then? If we decide now to build a virtual hosting farm on 0.12, will we be able to use live migration in the future if we decide we want to upgrade to 0.13 or later? N. On 08/31/2010 02:24 PM, Avi Kivity wrote: It should work between 0.12 and 0.13, though. -- To unsubscribe from this list: send the line unsubscribe kvm in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Is it possible to live migrate guest OS'es between different versions of kvm/qemu-kvm?
Hi, I currently have a couple of Debian KVM servers with all a different version of kvm or qemu-kvm. I can live migrate a guest OS from one server to the other just fine, as long as the version of qemu-kvm is the same. (Thanks to Gleb Natapov who helped me solve my ARP announce problem yesterday) However, when I try to migrate a guest to a server running a newer (or older) version of qemu-kvm, I run into problems. I think this is because the xml configuration differs slightly between version. For example, if I try to migrate from a server running qemu-kvm 0.11.0 to one running qemu-kvm 0.12.4, I get the following error: virt01:~# virsh migrate --live testserver qemu+ssh://192.168.1.7/system error: internal error unable to reserve PCI address 0:0:3 When migrating from kvm 85 to qemu-kvm 0.11.0: virt02:~# virsh migrate --live testserver qemu+ssh://192.168.1.2/system error: Unknown failure Migrating one from 0.12.4 to 0.11.0 just completely breaks libvirt, forcing me to kill -9 libvirtd and the kvm instance, etc. I believe this is caused in part because different versions of qemu-kvm need different xml configurations. To run my testserver on 0.12.4 for example, I need to delete the lines with the PCI id's, just to be able to start the it. So, is there a way to make this work? Perhaps without libvirt? Or tell libvirt to not send the config file when doing a live migrate, and use the xml in /etc/libvirt/qemu instead somehow? Thanks in advance, Nils -- To unsubscribe from this list: send the line unsubscribe kvm in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
KVM doesn't send an arp announce after live migrating a domain
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? :-) ) 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 majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: KVM doesn't send an arp announce after live migrating a domain
On 08/25/2010 10:38 AM, Gleb Natapov wrote: qemu sends gratuitous ARP after migration. Check forward delay setting on your bridge interface. It should be set to zero. Aha! That fixed it. Turns out that debian bridge-utils sets the default to 15 for bridges. Manually setting it to 0 with 'brctl setfd br0 0' or setting the 'bridge_fd' parameter to 0 in /etc/network/interfaces solves the issue. Thanks for the help! Nils -- To unsubscribe from this list: send the line unsubscribe kvm in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
