Tape Devices
View status and configuration information for tape-based storage devices.
The table shows the tape libraries that are defined to the servers that are managed by the Operations Center. A library is a collection of one or more drives and robotic devices, which can be used to access storage volumes.
If a library is shared, it is defined on multiple servers. Therefore, the library information appears across multiple table rows. The table shows one row for each server on which the library is defined, and the information is applicable only to the library definition on that server. The Library Management column shows whether the server is the library manager or a library client.
An automated library might contain different device types. For example, a StorageTek L40 library might contain Digital Linear Tape (DLT) drives and Linear Tape-Open (LTO) drives. If a library contains different device types, the library information appears across multiple table rows. The table shows one row for each device type.
The following actions and status indicators are shown on the page:
- All Devices Alerts
- The number of active and inactive alerts for tape devices and disk devices.
- Details
- Use the details notebook to monitor tape usage, to view or change library properties, and to view drive status and configuration information.
- Status
- The Status summary reflects the state of the device class.
Warning and error states are triggered when defined threshold values are exceeded. Examples of state thresholds include the percentage of drives that the server is polling, or the percentage of paths that are offline. The percentage values in the following state descriptions are based on the default threshold settings.
Tip: To display the current threshold settings for a server, issue the QUERY STATUSTHRESHOLD command. To modify the threshold settings, use the UPDATE STATUSTHRESHOLD command.The following states can be shown: - Robotics
Specifies whether the server can access the library robotics. The robotics include the cartridge accessor and any associated mechanisms that move a tape cartridge within the tape library. The server accesses the library robotics though the library path. The library path identifies the device special file for the tape device, and gives the server control of the library robotics.
The following states can be shown:- Scratch Tapes
- The number of scratch tape volumes that are available for the
server to use. A scratch tape is a tape that is empty
or contains no valid data.
Blank tape cartridges can be checked into a library as scratch volumes. If a storage pool of the library's device class is configured to request scratch volumes, the server can satisfy the mount requests if scratch volumes are available. For shared libraries, the library manager and any library client can use the library's scratch volumes to satisfy requests from storage pools.
When data is written to a scratch volume, its status is changed to private, and it is defined as part of the storage pool for which the mount request was made. The volume is not included in the Scratch Tape count, but is included in the Private Volumes count.
When valid data is moved from the volume and the volume is reclaimed, the volume returns to scratch status and can be reused. If the library drives use Write Once Read Many (WORM) tape media, the tapes cannot be reclaimed.
You can use the following techniques to make more scratch volumes available:- If you have blank tape cartridges and available slots in the library, you can check in the tape cartridges.
- Configure storage pools for reclamation processing. After expired data is removed from tape volumes, reclamation processing can consolidate the remaining unexpired data onto fewer tape volumes.
- Drives in Use
- The number of drives that are being used by the server, or by
another server in a shared library. A drive is in use if it is reserved
for a mount request or if it is loaded and the server is performing
operations in the drive.
Compare this value with the status information in the Drives column to determine how many drives are available for the server to use.
- Drives
- The number of drives that the server can access, and the online
status of the drive. To access a drive, a path from the server to
the drive must be defined and available. If the server detects a problem
with the drive, the server can take the drive offline. An administrator
can also take a drive offline during maintenance or repair operations
to indicate that the drive is not available for use.
If the library is shared, this drive information is shown only for the library manager, and is not shown for library clients.
To change the state of a drive, use the UPDATE DRIVE command.
For more information about the drives that are defined in a library, including each drive's online state, open the Drives page of the details notebook.
- Paths
- The number of library and drive paths that are defined for the
library. Paths connect the server to the library and to the individual
drives in the library. Paths are defined to access the library and
drives through device special files in the file system.
If the server is unable to access a defined library or drive, it takes the path offline. A library path might be offline because the tape device is powered off or because of a network problem. A drive path might be offline because of problems with the drive or the network.
If the library is shared, this path information is shown only for the library manager, and is not shown for library clients.
A path can also be set offline by using the UPDATE PATH command.
If paths are offline, you can take the following actions:- To determine if the library is offline, view the status in the Robotics column.
- For more information on the drive paths that are offline, open the Drives page of the details notebook.
- To view alerts that might explain the problem, click All Device Alerts.
- To view activity log messages that might explain the problem, use the QUERY ACTLOG command. Specify the tape device name on the Search parameter to display only messages about the tape device
To change the state of a path, use the UPDATE PATH command.
- Storage Pools
- The number of storage pools that are defined to the server for
the device class. Click the value in this column to open the Storage
Pools page for these storage pools.
On the Storage Pools page, the Max Scratch column shows the maximum number of scratch volumes that the storage pool can request. The Scratch Available column shows the remaining number of scratch volumes that the storage pool can request.
- Private Volumes
- The number of private volumes that are owned by the server. Private volumes are volumes that are either already assigned to storage pools, or were checked in by the server as private.
- Library Type
- The type of tape storage devices collected in this library. This
value is one of the following library types:
- ACSLS
- Specifies that the library is a StorageTek library that is controlled by StorageTek Automated Cartridge System Library Software (ACSLS).
- MANUAL
- Specifies that the library is not automated. When volumes must be mounted on drives in this type of library, messages are sent to operators. This type of library is used with stand-alone drives.
- SCSI
- Specifies that the library has a SCSI-controlled media changer device. A media changer device is used to mount volumes on drives in this type of library.
- SHARED
- Specifies that the library is shared with another server over a storage area network or a dual SCSI connection to library drives. This library type is shown for library clients in a shared library. To determine the type of tape storage devices that are collected in the library, view the library type of the library manager server.
- VTL
- Specifies that the library has a SCSI-controlled media changer device that is represented by a virtual tape library. A media changer device is used to mount volumes on drives in this type of library.
- Library Management
In a shared library, one server is set up as the library manager and controls library operations such as mount and dismount. The library manager also controls volume ownership and manages the library inventory. Other servers are set up as library clients and use server-to-server communications to contact the library manager and request resources.
A library can also be managed by an external media management system, such as the
This column applies only to shared libraries and external libraries. This column does not apply to libraries that are defined on, and controlled by, only one server.
The following values can be shown:- Client of library_manager
- The library is shared, and the server is a library client of library_manager.
- External
- The library is managed by an external media management system, such as the IBM® Tape System Library Manager (TSLM).
- Library manager
- The library is shared, and the server is the library manager.
For more information about managing storage devices or about using IBM Spectrum Protect commands, see the IBM Spectrum Protect documentation.