The following will show the procedure to remove a volume. This example the volume is a VMFS volume presented to ESXi hosts. First remove the volume from the ESXi hosts.

To do this first migrate any live VMs running on the VMFS datastore and also browse the datastore to check for any ESXi created folders that could still be in use - folders such as vsantraces / HA / scratch partitions. Once you are happy all data has been migrated right click the datastore - Unmount

Once unmounted the datastore will be labelled Inactive. Once complete right click the datastore - Remove

Now login to the Dell EQL - Volumes. Locate the volume just removed from ESXi - right click - Set Offline

Once complete right click - Delete Volume

The volume will be moved to a recycle bin, to free up the space the volume must also be cleared from the recycle bin. Select Volumes - Manage recovery bin

Delete the volumes from here, once emptied out of the recycle bin the data will be lost.