I/O to the external volume from the open system host is in progress.

Stop I/O to the volume and un-mount the volume from the host.

Host I/O is forcibly stopped if you disconnect when I/O is in progress.

The external volume includes LDEVs used in pair operations with the following copy software products:

• ShadowImage
• Universal Replicator
• TrueCopy
• Thin Image
• Global-active device

Delete the pair.

You can disconnect without deleting a ShadowImage pair when pair status is PSUE or Suspend/SUSPER.

The external volume includes LDEVs registered to a Thin Image data pool.

Delete Thin Image data pool.

The external volume includes LDEVs registered to a Dynamic Provisioning pool volume (DP-VOL).

Perform all of the following operations on DP-VOLs associated with the external volume:

• Stop using the DP-VOLs.
• Use the Block LDEVs window to block the DP-VOLs.
• If the Data Direct Mapping attribute is enabled for the external volume, block only the related DP-VOL.
• When a virtual volume for which Compression or Deduplication and Compression is enabled is created from a DP pool, if a failure occurs in the pool-VOL registered in the pool, recover the failure of the pool-VOL. In addition, if a deduplication system data volume is created, block it.

The external volume includes LDEVs for which Volume Migration processing is in progress.

Delete the migration plans.

The external volume is used in a global-active device quorum disk.

Delete the quorum disk settings.