HP B6960-90078 manual Device Locking

Configuring and Using Backup Devices

Device Locking

	Device Locking
Internal Locking	The internal locking of backup devices prevents two Data Protector
	sessions from accessing the same physical device at the same time. For
	example, if one backup session is using a particular device, all other
	backup/restore sessions must wait for this device to become free before
	starting to use it. When a backup or restore session starts, the Data
	Protector locks the device, the drive, and the slot used for that session.
	Media sessions performing media operations such as initialization,
	scanning, verifying, copying, or importing also lock devices. During that
	time, no other operations can lock and use the device. If a media session
	cannot obtain a lock, the operation fails, and you have to retry the
	operation at a later time.
Locking When a	During a mount request of a backup or restore session, Data Protector
Mount Request Is	allows the device to be used for media management operations, such as
Issued	formatting a new medium.
	When the mount request is confirmed, the backup or restore session
	locks the device again and continues with the session.
Locking with Data	You can configure the same physical device many times with different
Protector	characteristics, simply by configuring devices with different device
	names.
	Since the internal locking operates on logical devices rather than on
	physical devices, a collision can occur if you specify one device name in
	one backup specification and another device name for the same physical
	device in another backup specification. Depending on the backup
	schedule, this may result in Data Protector trying to use the same
	physical device in several backup sessions at the same time. This can
	also happen when two device names are used in other operations, such as
	backup and restore, backup and scan, and so on.
	To prevent this collision, you can specify a virtual lock name in both
	device configurations. Data Protector then uses this lock name to check if
	the device is available, thus preventing collisions.
	If you configure two Data Protector backup devices that actually point to
	the same physical device, you are advised to specify the Lock Name in the
	advanced options for the two logical devices. Lock Name is the name that

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