[CentOS-virt] (KVM) How can I migrate VM in a non shared storage environment?
Hi, I have a server running CentOS 5.5 with KVM capabilities. I need to migrate all the VMs to another server with the exact same hardware specs. The problem is it is running on individual harddisks, not shared storage. What is the best way to migrate to minimise downtime? Thanks! YongSan ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt
Re: [CentOS-virt] (KVM) How can I migrate VM in a non shared storage environment?
One way would be to boot the VMs with a product like Acronis or Ghost, and create an image of the VM's drive(s). Then create a new VM on the 2nd server that has nics with the same MAC addresses as the old VM, and storage with the same sizes, and restore the image there. ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt
Re: [CentOS-virt] (KVM) How can I migrate VM in a non shared storage environment?
On 24/06/10 7:17 AM, "Poh Yong Hwang" wrote: > I have a server running CentOS 5.5 with KVM capabilities. I need to migrate > all the VMs to another server with the exact same hardware specs. The problem > is it is running on individual harddisks, not shared storage. What is the best > way to migrate to minimise downtime? I've had good success using dd and nc (netcat) to copy the contents of a disk or disk image from one machine to another, and verifying the copy was successful with a md5sum or sha1sum of both the original and copied disk. Kelvin ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt
Re: [CentOS-virt] (KVM) How can I migrate VM in a non shared storage environment?
I often use rsync -a for remote systems or cp -a for local systems. I've also used dd. You can have dd output to stdout, pipe it to ssh and have ssh output to dd on the other end. You can also connect to a SAN device on the source and dd from the local block device to the SAN device. Lots of ways to do it ;) Cheers, C.J. On Thu, 2010-06-24 at 10:52 -0400, Kelvin Edmison wrote: > > > On 24/06/10 7:17 AM, "Poh Yong Hwang" wrote: > > > I have a server running CentOS 5.5 with KVM capabilities. I need to migrate > > all the VMs to another server with the exact same hardware specs. The > > problem > > is it is running on individual harddisks, not shared storage. What is the > > best > > way to migrate to minimise downtime? > > I've had good success using dd and nc (netcat) to copy the contents of a > disk or disk image from one machine to another, and verifying the copy was > successful with a md5sum or sha1sum of both the original and copied disk. > > Kelvin > > ___ > CentOS-virt mailing list > CentOS-virt@centos.org > http://lists.centos.org/mailman/listinfo/centos-virt signature.asc Description: This is a digitally signed message part ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt
Re: [CentOS-virt] (KVM) How can I migrate VM in a non shared storage environment?
Create a new virtual machine on your storage. After this, boot some Linux distribution in your new virtual machine (I like SysrescueCD). Enable your ssh server, change the root password and so and back to your old virtual server and type: # dd if=/dev/sda | ssh root@(new_vm) "(dd of=/dev/sda)" Type the root password, shutdown the old VM and reboot your new vm. (PS: You don't need to shutdown the old vm to this proccess). I do this everytime, I don't like copy the HD files using cp, tar or rsync because it try to copy the /proc, /dev and a lot virtual devices. Using dd it copies just the HD bits, the boot sector, etc. 2010/6/24 C.J. Adams-Collier > I often use rsync -a for remote systems or cp -a for local systems. > I've also used dd. You can have dd output to stdout, pipe it to ssh and > have ssh output to dd on the other end. > > You can also connect to a SAN device on the source and dd from the local > block device to the SAN device. > > Lots of ways to do it ;) > > Cheers, > > C.J. > > > On Thu, 2010-06-24 at 10:52 -0400, Kelvin Edmison wrote: > > > > > > On 24/06/10 7:17 AM, "Poh Yong Hwang" wrote: > > > > > I have a server running CentOS 5.5 with KVM capabilities. I need to > migrate > > > all the VMs to another server with the exact same hardware specs. The > problem > > > is it is running on individual harddisks, not shared storage. What is > the best > > > way to migrate to minimise downtime? > > > > I've had good success using dd and nc (netcat) to copy the contents of a > > disk or disk image from one machine to another, and verifying the copy > was > > successful with a md5sum or sha1sum of both the original and copied disk. > > > > Kelvin > > > > ___ > > CentOS-virt mailing list > > CentOS-virt@centos.org > > http://lists.centos.org/mailman/listinfo/centos-virt > > > ___ > CentOS-virt mailing list > CentOS-virt@centos.org > http://lists.centos.org/mailman/listinfo/centos-virt > > -- Lucas Timm, Goiânia/GO. http://timmerman.wordpress.com (62) 9157-0789 ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt
Re: [CentOS-virt] (KVM) How can I migrate VM in a non shared storage environment?
Note, the -x argument will keep the copy to a single partition On Thu, 2010-06-24 at 14:12 -0300, Lucas Timm LH wrote: > Create a new virtual machine on your storage. After this, boot some > Linux distribution in your new virtual machine (I like SysrescueCD). > Enable your ssh server, change the root password and so and back to > your old virtual server and type: > > > # dd if=/dev/sda | ssh root@(new_vm) "(dd of=/dev/sda)" > > > Type the root password, shutdown the old VM and reboot your new vm. > > > (PS: You don't need to shutdown the old vm to this proccess). > > > I do this everytime, I don't like copy the HD files using cp, tar or > rsync because it try to copy the /proc, /dev and a lot virtual > devices. Using dd it copies just the HD bits, the boot sector, etc. > > 2010/6/24 C.J. Adams-Collier > I often use rsync -a for remote systems or cp -a for local > systems. > I've also used dd. You can have dd output to stdout, pipe it > to ssh and > have ssh output to dd on the other end. > > You can also connect to a SAN device on the source and dd from > the local > block device to the SAN device. > > Lots of ways to do it ;) > > Cheers, > > C.J. > > > On Thu, 2010-06-24 at 10:52 -0400, Kelvin Edmison wrote: > > > > > > On 24/06/10 7:17 AM, "Poh Yong Hwang" > wrote: > > > > > I have a server running CentOS 5.5 with KVM capabilities. > I need to migrate > > > all the VMs to another server with the exact same hardware > specs. The problem > > > is it is running on individual harddisks, not shared > storage. What is the best > > > way to migrate to minimise downtime? > > > > I've had good success using dd and nc (netcat) to copy the > contents of a > > disk or disk image from one machine to another, and > verifying the copy was > > successful with a md5sum or sha1sum of both the original and > copied disk. > > > > Kelvin > > > > ___ > > CentOS-virt mailing list > > CentOS-virt@centos.org > > http://lists.centos.org/mailman/listinfo/centos-virt > > > ___ > CentOS-virt mailing list > CentOS-virt@centos.org > http://lists.centos.org/mailman/listinfo/centos-virt > > > > > -- > Lucas Timm, Goiânia/GO. > http://timmerman.wordpress.com > > (62) 9157-0789 > signature.asc Description: This is a digitally signed message part ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt
Re: [CentOS-virt] (KVM) How can I migrate VM in a non shared storage environment?
This can be useful in some cases: http://www.bouncybouncy.net/ramblings/posts/xen_live_migration_without_shared_storage/ With the blocksync.py script on that page you can first make a copy of the block device while the VM is still running. Then shut down the VM and make another run only this time you only have to copy over the bits that have changed during the previous sync. Depending on HD/CPU/Net performance this can reduce the downtime a bit. Regards, Dennis On 06/24/2010 11:22 PM, C.J. Adams-Collier wrote: > Note, the -x argument will keep the copy to a single partition > > On Thu, 2010-06-24 at 14:12 -0300, Lucas Timm LH wrote: >> Create a new virtual machine on your storage. After this, boot some >> Linux distribution in your new virtual machine (I like SysrescueCD). >> Enable your ssh server, change the root password and so and back to >> your old virtual server and type: >> >> >> # dd if=/dev/sda | ssh root@(new_vm) "(dd of=/dev/sda)" >> >> >> Type the root password, shutdown the old VM and reboot your new vm. >> >> >> (PS: You don't need to shutdown the old vm to this proccess). >> >> >> I do this everytime, I don't like copy the HD files using cp, tar or >> rsync because it try to copy the /proc, /dev and a lot virtual >> devices. Using dd it copies just the HD bits, the boot sector, etc. >> >> 2010/6/24 C.J. Adams-Collier >> I often use rsync -a for remote systems or cp -a for local >> systems. >> I've also used dd. You can have dd output to stdout, pipe it >> to ssh and >> have ssh output to dd on the other end. >> >> You can also connect to a SAN device on the source and dd from >> the local >> block device to the SAN device. >> >> Lots of ways to do it ;) >> >> Cheers, >> >> C.J. >> >> >> On Thu, 2010-06-24 at 10:52 -0400, Kelvin Edmison wrote: >> > >> > >> > On 24/06/10 7:17 AM, "Poh Yong Hwang" >> wrote: >> > >> > > I have a server running CentOS 5.5 with KVM capabilities. >> I need to migrate >> > > all the VMs to another server with the exact same hardware >> specs. The problem >> > > is it is running on individual harddisks, not shared >> storage. What is the best >> > > way to migrate to minimise downtime? >> > >> > I've had good success using dd and nc (netcat) to copy the >> contents of a >> > disk or disk image from one machine to another, and >> verifying the copy was >> > successful with a md5sum or sha1sum of both the original and >> copied disk. >> > >> > Kelvin >> > >> > ___ >> > CentOS-virt mailing list >> > CentOS-virt@centos.org >> > http://lists.centos.org/mailman/listinfo/centos-virt >> >> >> ___ >> CentOS-virt mailing list >> CentOS-virt@centos.org >> http://lists.centos.org/mailman/listinfo/centos-virt >> >> >> >> >> -- >> Lucas Timm, Goiânia/GO. >> http://timmerman.wordpress.com >> >> (62) 9157-0789 >> > > > > ___ > CentOS-virt mailing list > CentOS-virt@centos.org > http://lists.centos.org/mailman/listinfo/centos-virt ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt
Re: [CentOS-virt] (KVM) How can I migrate VM in a non shared storage environment?
+1 for dd + nc over ssh if necessary. This process can and probably will saturate your ethernet interface, so depending upon the amount of traffic the box pushes on the public interface the size of the partition and other factors, sometimes i add a crossover cable between unused interfaces on the 2 boxes and run the process over that interface, so it doesn't impact the running vms. Cheers -Chris On 6/24/2010 9:00 AM, centos-virt-requ...@centos.org wrote: > Message: 3 > Date: Thu, 24 Jun 2010 10:52:57 -0400 > From: Kelvin Edmison > Subject: Re: [CentOS-virt] (KVM) How can I migrate VM in a non shared > storage environment? > To: Discussion about the virtualization on CentOS > > Message-ID: > Content-Type: text/plain; charset="US-ASCII" > > > > > On 24/06/10 7:17 AM, "Poh Yong Hwang" wrote: > >> I have a server running CentOS 5.5 with KVM capabilities. I need to migrate >> all the VMs to another server with the exact same hardware specs. The problem >> is it is running on individual harddisks, not shared storage. What is the >> best >> way to migrate to minimise downtime? > > I've had good success using dd and nc (netcat) to copy the contents of a > disk or disk image from one machine to another, and verifying the copy was > successful with a md5sum or sha1sum of both the original and copied disk. > > Kelvin > > > > -- > > ___ > CentOS-virt mailing list > CentOS-virt@centos.org > http://lists.centos.org/mailman/listinfo/centos-virt > > > End of CentOS-virt Digest, Vol 34, Issue 13 > *** ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt
Re: [CentOS-virt] (KVM) How can I migrate VM in a non shared storage environment?
If you do it often, you might consider listening for ssh connections on a separate port and using tc to keep things from getting out of hand: http://linux.die.net/man/8/tc Cheers, C.J. On Mon, 2010-06-28 at 09:17 -0700, Christopher Hunt wrote: > +1 for dd + nc over ssh if necessary. > > This process can and probably will saturate your ethernet interface, so > depending upon the amount of traffic the box pushes on the public > interface the size of the partition and other factors, sometimes i add a > crossover cable between unused interfaces on the 2 boxes and run the > process over that interface, so it doesn't impact the running vms. > > Cheers > -Chris > > On 6/24/2010 9:00 AM, centos-virt-requ...@centos.org wrote: > > > Message: 3 > > Date: Thu, 24 Jun 2010 10:52:57 -0400 > > From: Kelvin Edmison > > Subject: Re: [CentOS-virt] (KVM) How can I migrate VM in a non shared > > storage environment? > > To: Discussion about the virtualization on CentOS > > > > Message-ID: > > Content-Type: text/plain; charset="US-ASCII" > > > > > > > > > > On 24/06/10 7:17 AM, "Poh Yong Hwang" wrote: > > > >> I have a server running CentOS 5.5 with KVM capabilities. I need to migrate > >> all the VMs to another server with the exact same hardware specs. The > >> problem > >> is it is running on individual harddisks, not shared storage. What is the > >> best > >> way to migrate to minimise downtime? > > > > I've had good success using dd and nc (netcat) to copy the contents of a > > disk or disk image from one machine to another, and verifying the copy was > > successful with a md5sum or sha1sum of both the original and copied disk. > > > > Kelvin > > > > > > > > -- > > > > ___ > > CentOS-virt mailing list > > CentOS-virt@centos.org > > http://lists.centos.org/mailman/listinfo/centos-virt > > > > > > End of CentOS-virt Digest, Vol 34, Issue 13 > > *** > ___ > CentOS-virt mailing list > CentOS-virt@centos.org > http://lists.centos.org/mailman/listinfo/centos-virt signature.asc Description: This is a digitally signed message part ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt
Re: [CentOS-virt] (KVM) How can I migrate VM in a non shared storage environment?
Hi All, Thanks for all your suggestion. Just a check, if i have a full backup on the server but due to the different specs of the hardware so i am unable to do a bare metal restore, can i just dump all the folders under /var/lib/libvirt which also includes the images folder? Will it work that way? Here is the folders in libvirt: [r...@pop-kvm-web libvirt]# ls boot images iptables network qemu Thanks! yongsan On Tue, Jun 29, 2010 at 12:27 AM, C.J. Adams-Collier wrote: > If you do it often, you might consider listening for ssh connections on > a separate port and using tc to keep things from getting out of hand: > > http://linux.die.net/man/8/tc > > Cheers, > > C.J. > > On Mon, 2010-06-28 at 09:17 -0700, Christopher Hunt wrote: > > +1 for dd + nc over ssh if necessary. > > > > This process can and probably will saturate your ethernet > interface, so > > depending upon the amount of traffic the box pushes on the public > > interface the size of the partition and other factors, sometimes i add a > > crossover cable between unused interfaces on the 2 boxes and run the > > process over that interface, so it doesn't impact the running vms. > > > > Cheers > > -Chris > > > > On 6/24/2010 9:00 AM, centos-virt-requ...@centos.org wrote: > > > > > Message: 3 > > > Date: Thu, 24 Jun 2010 10:52:57 -0400 > > > From: Kelvin Edmison > > > Subject: Re: [CentOS-virt] (KVM) How can I migrate VM in a non shared > > > storage environment? > > > To: Discussion about the virtualization on CentOS > > > > > > Message-ID: > > > > > Content-Type: text/plain; charset="US-ASCII" > > > > > > > > > > > > > > > On 24/06/10 7:17 AM, "Poh Yong Hwang" wrote: > > > > > >> I have a server running CentOS 5.5 with KVM capabilities. I need to > migrate > > >> all the VMs to another server with the exact same hardware specs. The > problem > > >> is it is running on individual harddisks, not shared storage. What is > the best > > >> way to migrate to minimise downtime? > > > > > > I've had good success using dd and nc (netcat) to copy the contents of > a > > > disk or disk image from one machine to another, and verifying the copy > was > > > successful with a md5sum or sha1sum of both the original and copied > disk. > > > > > > Kelvin > > > > > > > > > > > > -- > > > > > > ___ > > > CentOS-virt mailing list > > > CentOS-virt@centos.org > > > http://lists.centos.org/mailman/listinfo/centos-virt > > > > > > > > > End of CentOS-virt Digest, Vol 34, Issue 13 > > > *** > > ___ > > CentOS-virt mailing list > > CentOS-virt@centos.org > > http://lists.centos.org/mailman/listinfo/centos-virt > > > ___ > CentOS-virt mailing list > CentOS-virt@centos.org > http://lists.centos.org/mailman/listinfo/centos-virt > > ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt
