Administrator's Guide

Moving Files from One Volume to Another Volume

You can move files from one volume to another volume in the same or a different storage pool. The volumes can be onsite volumes or offsite volumes. During normal operations, you do not need to move data. You might need to move data in some situations, for example, when you need to salvage any readable data from a damaged ADSM volume.

During the data movement process, the server:

• Moves any readable files to available volumes in the specified destination storage pool

• Deletes any cached copies from a disk volume

• Attempts to bypass any files that previously have been marked as damaged

During the data movement process, users cannot access the volume to restore or retrieve files, and no new files can be written to the volume.

Note:

Files in a copy storage pool do not move when primary files are moved.

Task	Required Privilege Class
Move files from a volume in any storage pool to an available volume in any storage pool	System or unrestricted storage
Move files from one volume to an available volume in any storage pool to which you are authorized	Restricted storage

Moving Data to Other Volumes in the Same Storage Pool

Moving files from one volume to other volumes in the same storage pool is useful:

• When you want to free up all space on a volume so that it can be deleted from the ADSM server

  See "Deleting Storage Pool Volumes" for information about deleting backed-up, archived, or space-managed data before you delete a volume from a storage pool.

• When you need to salvage readable files from a volume that has been damaged

• When you want to delete cached files from disk volumes

  If you want to force the removal of cached files, you can delete them by moving data from one volume to another volume. During the move process, ADSM deletes cached files remaining on disk volumes.

If you move data between volumes within the same storage pool and you run out of space in the storage pool before all data is moved from the target volume, then you cannot move all the data from the target volume. In this case, consider moving data to available space in another storage pool as described in "Moving Data to Another Storage Pool".

Moving Data to Another Storage Pool

You can move all data from a volume in one storage pool to volumes in another storage pool. When you specify a target storage pool that is different than the source storage pool, ADSM uses the storage hierarchy to move data if more space is required.

Note:

Data cannot be moved from a primary storage pool to a copy storage pool. Data in a copy storage pool cannot be moved to any other storage pool.

You can move data from random access storage pools to sequential access storage pools. For example, if you have a damaged disk volume and you have a limited amount of disk storage space, you could move all files from the disk volume to a tape storage pool. Moving files from a disk volume to a sequential storage pool may require many volume mount operations if the target storage pool is collocated. Ensure that you have sufficient personnel and media to move files from disk to sequential storage.

Moving Data from an Offsite Volume in a Copy Storage Pool

You can move data from offsite volumes without bringing the volumes onsite. Processing of the MOVE DATA command for primary storage pool volumes does not affect copy storage pool files.

Processing of the MOVE DATA command for volumes in copy storage pools is similar to that of primary storage pools, with the following exceptions:

• Most volumes in copy storage pools may be set to an access mode of offsite, making them ineligible to be mounted. During processing of the MOVE DATA command, valid files on offsite volumes are copied from the original files in the primary storage pools. In this way, valid files on offsite volumes are copied without having to mount these volumes. These new copies of the files are written to another volume in the copy storage pool.

• With the MOVE DATA command, you can move data from any primary storage pool volume to any primary storage pool. However, you can move data from a copy storage pool volume only to another volume within the same copy storage pool.

When you move files from a volume marked as offsite, ADSM:

1. Determines which files are still active on the volume from which you are moving data

2. Obtains these files from a primary storage pool or from another copy storage pool

3. Copies the files to one or more volumes in the destination copy storage pool

Procedure for Moving Data

1. Before you move files from a volume, complete the following steps:

   • If you want to ensure that no new files are written to a volume after you move data from it, change the volume's access mode to read-only. This prevents the server from filling the volume with data again as soon as data is moved. You might want to do this if you want to delete the volume.

     See "Updating Storage Pool Volumes" for information about updating the access mode of a storage pool volume.

   • Ensure sufficient space is available on volumes within the specified destination storage pool by:

     1. Querying the source storage volume to determine how much space is required on other volumes. See "Monitoring the Use of Storage Pool Volumes" for information about requesting information about a storage volume.

     2. Querying the specified destination storage pool to ensure there is sufficient capacity to store the files being moved. See "Monitoring the Use of Storage Pool Space" for information about querying a storage pool.

     If you need more storage space, define volumes or increase the maximum number of scratch volumes in the specified destination storage pool. See "Defining Storage Pool Volumes" for preparing volumes to be used for server storage.

   • If you are moving files from a volume in a sequential storage pool to another volume in the same storage pool, ensure that the mount limit of the device class associated with the storage pool is greater than one.

     See "Requesting Information about a Device Class" for requesting information about the mount limit value for the device class.

   • If you are moving files from a tape volume to a tape storage pool, ensure that the two tape drives required are available.

2. Move the data using the MOVE DATA command.

   For example, to move the files stored in the /dev/vol3 volume to any available volume in the STGTMP1 storage pool, enter:

   move data /dev/vol3 stgpool=stgtmp1
   

   When you move data from a volume, the server starts a background process and sends informational messages, such as:

   +--------------------------------------------------------------------------------+
   |ANR1140I Move Data process started for volume /dev/vol3                         |
   |(process ID 32).                                                                |
   +--------------------------------------------------------------------------------+

   
   

   The command may be run in the foreground on an administrative client by issuing the command with the WAIT=YES parameter.

Requesting Information about the Data Movement Process

To request information on the data movement process, enter:

query process

Figure 33 shows an example of the report that you receive about the data movement process.

Figure 33. Information on the Data Movement Process

+--------------------------------------------------------------------------------+
|                                                                                |
| Process Process Description  Status                                            |
|  Number                                                                        |
|-------- -------------------- ------------------------------------------------- |
|      32 Move Data            Volume /dev/vol3, (storage pool BACKUPPOOL),      |
|                               Target Pool STGTMP1, Moved Files: 49, Moved      |
|                               Bytes: 9,121,792, Unreadable Files: 0,           |
|                               Unreadable Bytes: 0. Current File (bytes):       |
|                               3,522,560                                        |
|                                                                                |
|                               Current output volume: VOL1.                     |
+--------------------------------------------------------------------------------+

Monitoring the Movement of Data between Volumes

You can query the server for volume information to monitor the movement of data between volumes. For example, to see how much data has moved from the source volume in the move operation example, enter:

query volume /dev/vol3 stgpool=backuppool

Near the beginning of the move process, querying the volume from which data is being moved gives the following results:

+--------------------------------------------------------------------------------+
|Volume Name         Storage       Device         Estimated    %Util     Volume  |
|                    Pool Name     Class Name      Capacity              Status  |
|                                                      (MB)                      |
|---------------     -----------   ----------     ---------    -----    -------- |
|/dev/vol3           BACKUPPOOL    DISK                15.0     59.9    On-Line  |
|                                                                                |
+--------------------------------------------------------------------------------+

Querying the volume to which data is being moved (VOL1, according to the process query output) gives the following results:

+--------------------------------------------------------------------------------+
|Volume Name         Storage       Device         Estimated    %Util     Volume  |
|                    Pool Name     Class Name      Capacity              Status  |
|                                                      (MB)                      |
|----------------    -----------   ----------     ---------    -----    -------- |
|VOL1                STGTMP1       8500DEV          4,944.0      0.3    Filling  |
+--------------------------------------------------------------------------------+

At the end of the move process, querying the volume from which data was moved gives the following results:

+--------------------------------------------------------------------------------+
|Volume Name         Storage       Device         Estimated    %Util     Volume  |
|                    Pool Name     Class Name      Capacity              Status  |
|                                                      (MB)                      |
|----------------    ----------    ----------     ---------    -----    -------- |
|/dev/vol3           BACKUPPOOL    DISK                15.0      0.0    On-Line  |
+--------------------------------------------------------------------------------+