When using the Tape Backup function of AdvancedCopy Manager to back up data, a backup volume with the same capacity as the transaction volume is automatically selected from the registered backup volumes. If a specified backup volume is to be used to back up a given transaction volume, a "Device map file" (i.e., a file defining the correspondence between transaction and backup volumes) must be created.
Create a device map file anywhere on the Storage Server that performs backup. If you specify this file while performing backup, an operation that recognizes the backup destination is enabled.
Point
To manage multiple backup generations, multiple device map files must be prepared.
The device map file which can be used when backing up or starting synchronous processing should meet either of the following requirements:
An unused backup volume is specified, or
The backup volume used by the history data deleted by this backup is specified.
You should ensure that you configure and use the device map file appropriately, depending on how you are using the backup system with two or more backup volumes.
If the number of backup volumes that can be prepared for synchronized high-speed backup is only the same as the number of preservation generations, the backup operation can still be carried out by saving the backup volumes to secondary media, such as tapes, and then deleting history information.
In such cases, the device map file that is subsequently specified at the start of synchronous backup processing is the device map file specifying the backup volumes that become available for reuse when history information is deleted.
For a description of a device map file, refer to "Describing a device map file" in the "ETERNUS SF AdvancedCopy Manager Operator's Guide" for the operating system of the Storage Server.
