The absurdity of migrating a VM vs. restoring a VM from backup

AngryAdm

Member
Sep 5, 2020
145
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I have a few nodes.

I have a Domain controller on one node using 15GB storage space in a 220G RAW file where more than 90% is empty.
I attempt to migrate this to a different node... 3 hours later, still not done. I stop the process as my patience ran out.

I decide to Migrate it the fast way:
-Backup DC with PBS. 10 minuttes later.. done
-Detach drives from the VM and delete the disks. 30 seconds.. done
-Migrate the VM without disks (as I just deleted them) 30 seconds.. done
-Restore the VM from PBS 10 minuttes later.. done.

Why does it take 20 minuttes to do it the fast way, but 3 hours+(an unknown amount of time) to migrate the 15GB used space using the UI?

This does not make sense!
 
Last edited:

Denny

Active Member
Jul 28, 2016
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20
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I can't replicate your results. I have a 3 node cluster. Migration network is on a 10gig network with a small microtik switch. Moving a node with a single disk of 108G takes about 4.5 minutes.
 

fabian

Proxmox Staff Member
Staff member
Jan 7, 2016
8,424
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you haven't given details about what kind of storage you are using on either end, but it's likely some combination that needs to fully initialize/transfer the disk including empty blocks.. PBS and VMA backups will optimize that away.
 

fabian

Proxmox Staff Member
Staff member
Jan 7, 2016
8,424
1,679
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is an offline migration faster? can you post a task log?
 

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