Veeam Backup Failure after Hyper-V conversion to VMware

Relevant Errors:
 
Failed to prepare guest for hot backup. Error: VSSControl: -2147212529 Backup job failed.
Discovery phase failed.
Cannot add volumes to the snapshot set.
Cannot add a volume to the snapshot set. Volume name: [\\?\Volume{xxxxxxxxxx}\].
Cannot add volume to the set of volumes that should be shadowed.
VSS error: VSS_E_UNEXPECTED_PROVIDER_ERROR. Code:0x8004230f



This occurs when Guest Processing File System Indexing is enabled on the backup.

The fix for us was that the Hyper-V VSS provider was still installed. To remove this, all you need to do is:

1. Open Regedit
2. Browse to Computer\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\VSS\Providers\
3.  Find {74600e39-7dc5-4567-a03b-f091d6c7b092} (If you expand it, the default value is "Hyper-V IC Software Shadow Copy Provider")
4. Delete the entirety of the {74600e39-7dc5-4567-a03b-f091d6c7b092} key (NOT the VSS or Providers keys)
5. Reboot

Run the backup again, and this time it should complete. If not, or if that key doesn't exist, then you have an unrelated VSS issue and you can get further info from command prompt with the following command:
vssadmin list  writers

Enable NFS 4.1 on Synology

Enable SSH from Control Panel -> Terminal and SNMP
Connect using Putty, login with your Synology admin credentials
Enter the following commands:
cd /usr/syno/etc/rc.sysv
sudo vi S83nfsd.sh

Go down to line 90, position your cursor at the N on the line "/usr/sbin/nfsd $N"
Press "i" to begin editing
Change the line to:
/usr/sbin/nfsd $N -V 4.1
Press Esc to finish editing

Type the following to save:
:w

Type the following to quit:
:q

The following will restart the NFS service:
sudo ./S83nfsd.sh restart

Now, if you run the following command you should see NFS 4.1 enabled:
sudo cat /proc/fs/nfsd/versions

ESXi Reclaim raw storage from thin provisioned storage

This is to reclaim raw storage after having shrunk back thin provisioned volumes.

(Example, you migrate a VM to a new datastore, leaving an empty datastore in VMWare but still containing allocated space on the SAN)

ESXi 5.0-5.1

vmkfstools -y percentage_of_deleted_blocks_to_reclaim

I usually do 98 so:
vmkfstools -y 98

ESXi 5.5

esxcli storage vmfs unmap -l MyDatastore

-l is identifying the datastore by label, you enter the name, and away it goes.

ESXi 6.5

In 6.5 as long as your datastore is V6 it will unmap slowly in the background automatically. For legacy datastores, you will still manually have to initiate it.
Source:
http://vsphere-land.com/news/automatic-space-reclamation-unmap-is-back-in-vsphere-6-5.html