Administrator's Guide


Managing Media Mount Operations

ADSM generates an operator request when the ADSM server requires some kind of action with a drive or library. For example, when ADSM requires a volume mount in a manual library, it generates a request. The server sends mount request status messages to the server console and to all administrative clients that have been started with either the mount mode or the console mode parameter.

In many cases, an operator request has a time limit. If the requested action is not performed within the time limit, the operation times out and fails.

For most types of requests, such as volume mounts, the server detects when the operator performs the action. The operator does not usually need to respond to the ADSM server after carrying out the requested activity. However, sometimes the server cannot detect the completion of the requested action. When the server requires a reply, the message that is displayed by the server requests that the operator reply when the activity has been completed. For example, a request to mount a scratch volume requires that the operator reply when a scratch volume has been placed in the drive. ADSM waits for a reply to prevent the use of the wrong volume.

For most of the requests associated with automated (SCSI) libraries, the server cannot automatically detect when a requested activity has been completed. For such requests, the operator must use the REPLY command on the command line of an ADSM administrative client.

Using the Administrative Client for Mount Messages

The server sends mount request status messages to the server console and to all administrative clients that have been started with either the special mount mode or console mode parameter. For example, to start the OS/2 administrative client in mount mode, enter this command:

> dsmadmc -mountmode

Requesting Information about Pending Operator Requests


Task Required Privilege Class
Request information about operator requests or mounted volumes Any administrator

You can get information about pending operator requests either by using the QUERY REQUEST command or by checking the mount message queue on an administrative client started in mount mode.

When you issue the QUERY REQUEST command, ADSM displays requested actions and the amount of time remaining before the requests time out. For example, you enter the command as follows:

query request

The following shows an example of a response to the command:


+--------------------------------------------------------------------------------+
|ANR8352I Requests outstanding:                                                  |
|ANR8326I 001: Mount 8MM volume DSM001 R/W in drive TAPE01 (/dev/mtx)            |
|of MANUAL8MM within 60 minutes.                                                 |
|                                                                                |
+--------------------------------------------------------------------------------+

Replying to Operator Requests


Task Required Privilege Class
Reply to operator requests Operator

When the server requires that an explicit reply be provided when a mount request is completed, you can reply via the ADSM REPLY command. The first parameter for this command is the request identification number that tells the server which of the pending operator requests has been completed. This 3-digit number is always displayed as part of the request message. It can also be obtained by issuing a QUERY REQUEST command. If the request requires the operator to provide a device to be used for the mount, the second parameter for this command is a device name.

For example, enter the following command to respond to request 001 for tape drive TAPE01:

reply 1

Canceling an Operator Request


Task Required Privilege Class
Cancel operator requests Operator

If a mount request for a manual library cannot be satisfied, you can issue the CANCEL REQUEST command. This command forces the server to cancel the request and cause the operation that needed the requested volume to fail.

The CANCEL REQUEST command must include the request identification number. This number is included in the request message. You can also obtain it by issuing a QUERY REQUEST command, as described in "Requesting Information about Pending Operator Requests".

You can specify the PERMANENT parameter if you want to mark the requested volume as UNAVAILABLE. This process is useful if, for example, the volume has been moved to a remote site or is otherwise inaccessible. By specifying PERMANENT, you ensure that the server does not try to mount the requested volume again.

For most of the requests associated with automated (SCSI) libraries, an operator must perform a hardware or system action to cancel the requested mount. For such requests, the ADSM CANCEL REQUEST command is not accepted by the server.

Responding to Requests for Volume Check-In

If the server cannot find a particular volume it needs to be mounted in an automated library, the server requests that the operator check in the volume. For example, a client requests that an archived file be retrieved. The file was archived in a storage pool in an automated library. The server looks for the volume containing the file in the automated library, but cannot find the volume. The server then requests that the volume be checked in.

If the volume that the server requests is available, put the volume in the library and check in the volume using the normal procedures ("Informing the Server about New Volumes in a Library").

If the volume requested is unavailable (lost or destroyed), update the access mode of the volume to UNAVAILABLE by using the UPDATE VOLUME command. Then cancel the server's request for check-in by using the CANCEL REQUEST command. (Do not cancel the client process that caused the request.) To get the ID of the request to cancel, use the QUERY REQUEST command.

If you do not respond to the server's check-in request within the mount-wait period of the device class for the storage pool, the server marks the volume as unavailable.

Determining Which Volumes Are Mounted


Task Required Privilege Class
Request information about which volumes are mounted Operator

For a report of all volumes currently mounted for use by the server, you can issue the QUERY MOUNT command. The report shows which volumes are mounted, which drives have accessed them, and if the volumes are currently being used.

Dismounting an Idle Volume


Task Required Privilege Class
Request a volume dismount Operator

After a volume becomes idle, the server keeps it mounted for a time specified by the mount retention parameter for the device class. Using mount retention can reduce the access time if volumes are repeatedly used.

An administrator can explicitly request that an idle volume be dismounted by issuing the DISMOUNT VOLUME command. This command causes the server to dismount the named volume from the drive in which it is currently mounted.

For information about setting mount retention times, see "Mount Retention Period".


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