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Druva Documentation

When is thin disk backed up or restored as thick disk


This article applies to:

  • Product edition: Phoenix 

Applicable scenarios

A thin disk is backed up or restored as a thick disk in the following scenarios:

  • At the time of backup, CBT of the source VM was disabled. 
  • Source VM resides on NFS datastore during backup.For NFS datastores, Phoenix cannot perform a * query to find the allocated data blocks.  Hence, the Phoenix VMware Agent does not detect the sparse block and backs up the sparse block as a zero data block. Therefore, the thin disk is converted into a thick disk during restore.
  • At the time of backup, there was no sparse block present on the disk - Phoenix VMware agent does not change the disk type explicitly, but the change is from VMware when there is no sparse block on the disk of the restored VM.

See also

 VMware reference article:

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