bad performance ? do not support THIN provision HDD?

[seanlv]

I use Veeam BR to migrate a VM from vCenter to a standalone ESXi host.

vCenter is located on a remote site with high-speed WAN link.

Veeam BR and Standalone ESXi hosts are located in same site.


I tried to migrate a VM with THIN provisioned HDD (200GB, actual size is 15GB) via Veeam BR. I tried both Replication and Quick Migration feature. the result is below

1, Veeam do not support THIN provisioned HDD? (In Job detail I saw: Hard Disk 1(200.0GB) 41.0GB read at 22MB/s) I expect when read at 15GB, the task should be near finish, however, it's not, only 21% completed.

2, comparing with vCenter Convertor standalone (VCS), the BR's performance is bad enough. VCS used around 10 minuses and it took more than 1 hours if using BR to migrate the same VM

3, How can I keep the existing snapshot along with the VM, when performing migration from my vcenter to the standalone ESXi host?

thanks

[foggy]

Sean, I would guess that, since you are talking about existing snapshot, CBT cannot be enabled for this VM resulting in Veeam B&R reading the whole source disk during VM processing.

To be more specific, snapshots are not backed up and get consolidated into a single flat file during backup/replication. In case of existing snapshots, CBT could sometimes not work for VMs that have one or more snapshots before backup start (VMware limitation). Before running backup and replication jobs, it is recommended to delete VM snapshots, so that the job can enable CBT on all processed VMs.

Inability to enable CBT results in the fact that Veeam B&R has to read the whole disks to verify those blocks that need to be processed.

Apart from the snapshot issue, there's also a known problem with initial VMware CBT query that does not work reliably. This is covered in this topic in more detail.

If you need to migrate VM along with its snapshots, I recommend using the VM Copy job to copy the entire VM folder to the target location and register it in vSphere.

[tsightler]

If you need to migrate VM along with its snapshots, I recommend using the VM Copy job to copy the entire VM folder to the target location and register it in vSphere.

I think you might mean a File Copy job as I believe that a VM Copy job will not preserve snapshots since it still uses VADP API. File Copy basically just copies the files native, including any snapshot files, and you can register at the other site. There are some caveats to this, especially if the snapshots are created with memory state, since you can't always resume snapshots across different platforms.

[foggy]

I think you might mean a File Copy job as I believe that a VM Copy job will not preserve snapshots since it still uses VADP API.

Sure, thanks, Tom!