Configuring tape drives

You can connect tape drives to the storage agent to allow for LAN-free backups and restores of data.

Before you begin

Before you configure the tape drives, you must have the library manager and a library definition defined. Optionally, you can have library clients that are defined.

About this task

To configure tape drives to the storage agent, complete the following steps on the library manager:
1. Update the shared ACSLS, SCSI, VTL, or 3494 library by setting the SHARED parameter to YES.
2. Define paths from the storage agent server definition to each of the drives by using the DEFINE PATH command.

Windows operating systems When you use the DSMMAXSG utility, it increases the maximum transfer length for Host Bus Adapters (HBAs) and, so, the block size that is used by the Tivoli Storage Manager server for writing data to and getting data from certain types of tape drives. With this utility, the maximum supported block size is 256 KB. Depending on your system environment, the increase in block size can improve the rate at which IBM Storage Protect processes data for backups and restores and for archives and retrieves. However, the utility does not affect the generation of backup sets.

The only supported tape drives are drives that are attached to SCSI or Fibre Channel HBAs and that have the following device types:

3592
8MM_SAIT
DLT
ECARTRIDGE
LTO

Normally, the DSMMAXSG utility runs automatically as part of the Tivoli Storage Manager server and storage agent installation. However, if you install a new HBA on your system after server or storage agent installation or if you install a new version of an existing HBA device driver that resets the value of the maximum transfer size, you must run the utility manually to take advantage of the larger block size. To run the utility, enter the command:

dsmmaxsg

When you run this utility, it modifies one registry key for every HBA driver on your system. The name of the key is MaximumSGList.

Important: If data is backed up or archived to tape by using the 256 KB block size, the tape cannot be appended to or read from using an HBA that does not support the 256 KB block size. For example, if you use a 256 KB Windows system for backing up client data to the IBM Storage Protect server, you cannot restore the data by using a Windows system that supports a different transfer length. You must install an HBA that supports 256 KB transfers.