StorageTek 6 manual How the Scratch Redistribution Utility Functions

Scratch Redistribution

Scratch Redistribution Utility

The Scratch Redistribution utility provides you with a way to balance the number of scratch volumes across the ACS. It permits the redistribution of scratch volumes either:

•among LSMs implied by the specification of an ACS, or

•among the LSMs explicitly identified through an optional parameter.

This utility allows the user to select one media type and recording technique. If specified, scratch volume redistribution will be based on the MEDia and RECtech settings.

Notes: If neither MEDia nor RECtech is specified, volumes are redistributed without regard to media type or recording technique.

How the Scratch Redistribution Utility Functions

When only the ACS parameter is specified, the redistribution method transfers cartridges from LSMs with a greater number of scratch volumes to LSMs with a lesser number of scratch volumes. The process is repeated until the number of scratch volumes in each LSM is within the defined scratch tolerance level.

Distribution in an ACS containing a mix of LSMs (4410s, 9310s, 9360s, 9740s) is performed based on a percentage of scratch cartridges in the ACS. That is, the utility causes each LSM to have the same percentage of scratch tapes within the ACS as the LSM has cells within the ACS. For example, in an ACS where a 9310 LSM contains 80 percent of the cells within the ACS, 80 percent of the scratch tapes will reside in the 9310.

Note: The SL8500 is a standalone library and cannot be combined with any other LSM type.

After Scratch Redistribution is completed, only the specified LSMs contain scratch cartridges, if the LSM parameter was specified.

Concurrent redistributions among different ACSs are accomplished by multiple executions of this utility program.

Redistribution moves non-scratch cartridges to make space for scratch cartridges. The actual number of scratch cartridges moved may vary depending on the number of free cells and the number of scratch cartridges available.

Notes:

1.The Scratch Redistribution utility cannot be run concurrently with the Scratch Update utility, or when the Audit utility is being run in the same ACS as the Scratch Redistribution utility. An HSC message is generated, and the utility must be resubmitted.

2.Cartridges cannot be transferred to a frozen panel.

284VM/HSC 6.0 System Programmer’s Guide

1st ed., 6/30/04 - 312579601