The following describes all the -changesettings parameters:

• RB_DO_INTERMITTENT_UNLOADS - When this parameter is set to true (default), nbrb initiates unloads of the drives that have exceeded the media unload delay. Drives become available more quickly to jobs that require different media servers or different media than the job that last used the drive. However, the loaded media or drive pair may not be available for jobs with less priority in the prioritized evaluation queue that can use the drive or media without unload.

• RB_ENABLE_OPTIMIZATION - When this parameter is set to true, it serves as a performance tuning parameter for the Intelligent Resource Manager. This entry instructs NBRB to cache states of resource requests.

• RB_RESPECT_REQUEST_PRIORITY - Possible values for this parameter are true or false.

  When RB_RESPECT_REQUEST_PRIORITY is set to false (default), nbrb continues to evaluate jobs in the prioritized job queue. As a result, a job is likely to reuse a drive more quickly after the drive has been released. However, some lower priority jobs may receive drives before higher priority jobs. .

  When the parameter is set to true, nbrb restarts its evaluation queue at the top of the prioritized job queue after resources have been released.

• RB_BREAK_EVAL_ON_DEMAND - When a high priority request appears (for example, a tape span request, or a request for a synthetic or a duplication job), nbrb immediately interrupts the evaluation cycle. nbrb releases and unloads drives, if required before the evaluation cycle begins again.

  If the RB_BREAK_EVAL_ON_DEMAND parameter is set to true (default), interruptions of high priority jobs are not allowed and the evaluation cycle continues.

• RB_MAX_HIGH_PRIORITY_QUEUE_SIZE - Spanning requests and additional resources for an active duplication job are put in a special queue for priority processing. The RB_MAX_HIGH_PRIORITY_QUEUE_SIZE parameter sets the maximum number of requests that NetBackup allows in that queue. (Default: 100 requests.)

• RB_RELEASE_PERIOD - This parameter indicates the interval that NetBackup waits before it releases a resource. (Default: 180 seconds.)

• RB_CLEANUP_OBSOLETE_DBINFO - This parameter indicates the number of seconds that can elapse between the cleanup of obsolete information in the nbrb database. (Default: 60 seconds.)

• RB_MPX_GROUP_UNLOAD_DELAY - This parameter indicates the number of seconds that nbrb waits for a new job to appear before a tape is unloaded. (Default: 10 seconds.)

  This setting can help avoid unnecessary reloading of tapes and applies to all backup jobs. During user backups, nbrb uses the maximum value of RB_MPX_GROUP_UNLOAD_DELAY and the Media mount timeout host property setting when nbrb unmounts the tape.

• RB_RETRY_DELAY_AFTER_EMM_ERR - This parameter indicates how long NetBackup waits after an EMM error before it tries again. The error must be one where a retry is possible. For example, if a media server is down. (Default: 60 seconds.)

• RB_REEVAL_PENDING - This parameter indicates the number of seconds that can elapse between evaluations of the pending request queue. For example, a pending request queue can include, jobs awaiting resources. (Default: 60 seconds.)

• RB_REEVAL_PERIOD - This parameter indicates the time between evaluations if an outstanding request is not satisfied, and if no other requests or resources have been released. (Default: Five minutes must pass before the initial request is reevaluated.)