how do I migrate my KVM settings to a new desktop

JaredBusch

Scenario:

Fedora 25 + Cinnamon desktop (crashes when upgraded to 26 have not tried 27).
512GB SSD + 4TB HDD
Has KVM setup and single local Windows 10 VM with a bunch of in progress SQL development happening.
VM is located in /home/kvm_store
/home is mounted from the 4TB HDD

New Desktop
Fedora 27 + Cinnamon
256GB m.2 SSD + existing 4TB HDD will be relocated here
/home will remain mounted on the SSD
/home/kvm_store will be mounted to the HDD

User is the same. group ID was setup the same. what can I do to ensure that this VM continues to run?

Where are the KVM settings stored so I can migrated them?
Should I export the qcow2 and just set things up again?
Can I just move the disk and mount things and hope it powers up?

black3dynamite

Not sure how to backup KVM Host settings but here's how I backed up my VM

# Backup VM config and copy qcow2 image
sudo virsh dumpxml vmname > /media/backup/vmname.xml
sudo cp /home/user/libvirt/vmname.qcow2 /media/backup

# Restore VM config and copy qcow2 image
sudo cp /media/backup/vmname.qcow2 /home/user/libvirt
sudo virsh define --file /media/backup/vmname.xml

Obsolesce

@jaredbusch said in how do I migrate my KVM settings to a new desktop:

Scenario:

Fedora 25 + Cinnamon desktop (crashes when upgraded to 26 have not tried 27).
512GB SSD + 4TB HDD
Has KVM setup and single local Windows 10 VM with a bunch of in progress SQL development happening.
VM is located in /home/kvm_store
/home is mounted from the 4TB HDD

New Desktop
Fedora 27 + Cinnamon
256GB m.2 SSD + existing 4TB HDD will be relocated here
/home will remain mounted on the SSD
/home/kvm_store will be mounted to the HDD

User is the same. group ID was setup the same. what can I do to ensure that this VM continues to run?

Where are the KVM settings stored so I can migrated them?
Should I export the qcow2 and just set things up again?
Can I just move the disk and mount things and hope it powers up?

I've reloaded a few times from scratch, and all I ever did was copied the .qcow2 or .img file, nothing more.

Then reloaded, and copied back the virtual disks to where I wnat them... usually /home/uername/vms.

All I did was recreated the virtual machines using existing virtual disk and merrily went on my way.

If they don't boot, it's either because I forgot to change from IDE to SATA, or forgot to change from BIOS to UEFI. Other than that never had an issue.

Obsolesce

@jaredbusch said in how do I migrate my KVM settings to a new desktop:

Can I just move the disk and mount things and hope it powers up?

Yeah that's basically what I said above.

Move your disks, reload, move them back... re-setup your VM using existing disk.

Obsolesce

@black3dynamite said in how do I migrate my KVM settings to a new desktop:

Not sure how to backup KVM Host settings but here's how I backed up my VM

# Backup VM config and copy qcow2 image
sudo virsh vmname > /media/backup/vmname.xml
cp /home/user/libvirt/vmname.qcow2 /media/backup

# Restore VM config and copy qcow2 image
cp /media/backup/vmname.qcow2 /home/user/libvirt
sudo virsh define --file /media/backup/vmname.xml

I'll try this next time I need to reload or something. Looks a little quicker than setting things back up again manually.

black3dynamite

@tim_g said in how do I migrate my KVM settings to a new desktop:

I've updated my response with some corrections. To backup the VM config, you have to use sudo virsh dumpxml vmname and added sudo in front of cp.

JaredBusch

That is kind of what I expected, but I had not done it yet.

JaredBusch

@black3dynamite said in how do I migrate my KVM settings to a new desktop:

Not sure how to backup KVM Host settings but here's how I backed up my VM

# Backup VM config and copy qcow2 image
sudo virsh dumpxml vmname > /media/backup/vmname.xml
sudo cp /home/user/libvirt/vmname.qcow2 /media/backup

# Restore VM config and copy qcow2 image
sudo cp /media/backup/vmname.qcow2 /home/user/libvirt
sudo virsh define --file /media/backup/vmname.xml

This was perfect.

I did not copy the qcow2 as I moved the actual drive to the machine. I did edit the XML to point the vdisk to the new location.

Imported the xml, booted the VM.

Perfection.

FATeknollogee

Can you "virsh dumpxml vmname" while the vm is running?

black3dynamite

@fateknollogee said in how do I migrate my KVM settings to a new desktop:

Can you "virsh dumpxml vmname" while the vm is running?

Yes.