Dell PowerVault MD3420 - Manual (Page 113)

access to the virtual disk, and any attempt to write to the read-only target virtual disk results in a host I/O
error.
If you want hosts to have write access to the data on the target virtual disk, use the set
virtualDiskCopy command to disable the read-only attribute for the target virtual disk.
Virtual Disk Expansion
A Virtual Disk Expansion (VDE) is a modification operation that increases the capacity of a standard virtual
disk or a snapshot repository virtual disk. The increase in capacity is achieved by using the free capacity
that is available in the disk group of the standard virtual disk or the snapshot repository virtual disk.
This modification operation is considered to be ‘dynamic because you can continually access data on
disk groups, virtual disks, and physical disks throughout the entire operation.
A VDE operation can be performed on a primary virtual disk or a secondary virtual disk of a replication
relationship.
You cannot perform a VDE operation on a replication repository virtual disk.
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