IBM System Storage DS3000, Programming Manual

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v
A failed logical drive
v
A missing logical drive
v
A logical drive currently in a modification operation
v
A logical drive that is holding a Small Computer System Interface-2 (SCSI-2) reservation or a persistent
reservation
v
A logical drive that is a source logical drive or a target logical drive in another VolumeCopy that has a
status of In Progress, Pending, or Failed
Target Logical Drive
A target logical drive contains a copy of the data from the source logical drive. When a VolumeCopy is
started, data from the source logical drive is copied in its entirety to the target logical drive.
Attention: Possible loss of data access – A VolumeCopy overwrites data on the target logical drive.
Before you start a new operation, make sure that you no longer need the old data, or you have backed
up the old data on the target logical drive.
While the VolumeCopy has a status of In Progress, Pending, or Failed, the controllers reject read and
write requests to the target logical drive. After the VolumeCopy operation is finished, the target logical
drive automatically becomes read-only to the hosts, and write requests to the target logical drive are
rejected. You can change the Read-Only attribute after the VolumeCopy has completed or has been
stopped. (For more information about the Read-Only attribute, see “Viewing logical VolumeCopy
Properties” on page 9-6.)
The following logical drives are valid target logical drives:
v
A standard logical drive
v
The base logical drive of a disabled FlashCopy logical drive or failed FlashCopy logical drive
v
A primary logical drive that is participating in a remote-mirror pair
The following logical drives are not valid target logical drives:
v
The base logical drive of an active FlashCopy logical drive
v
A FlashCopy logical drive
v A mirror repository logical drive
v
A FlashCopy repository logical drive
v
A secondary logical drive in a remote-mirror pair
v
A failed logical drive
v
A missing logical drive
v
A logical drive with a status of Degraded
v
A logical drive that is currently in a modification operation
v
A logical drive that is holding a SCSI-2 reservation or a persistent reservation
v
A logical drive that is a source logical drive or a target logical drive in another VolumeCopy that has a
status of In Progress, Pending, or Failed
VolumeCopy and Persistent Reservations
You cannot use logical drives that hold persistent reservations for either a source logical drive or a target
logical drive. Persistent reservations are configured and managed through the server cluster software and
prevent other hosts from accessing the reserved logical drive. Unlike other types of reservations, a
persistent reservation reserves host access to the logical drive across multiple HBA host ports, which
provides various levels of access control.
9-2
IBM System Storage DS3000, DS4000, and DS5000: Command Line Interface and Script Commands Programming Guide