Dell PowerVault MD 32XX/36XX Series Storage Arrays CLI Guide

The virtual disk-to-LUN mapping enables you to define which host group or host has access to a particular virtual disk in the storage array.

After you create a virtual disk copy, the target virtual disk automatically becomes read‑only to hosts to ensure that the data is preserved. Hosts that have been mapped to a target virtual disk do not have write 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.