Drive Booking Services function

Purpose

ThruPut Manager Drive Booking Services (DBS) provides two related but distinct functions:

• The management of jobs that require tape drives, real or virtual. The drives that are managed represent all the devices that are available to batch processing in a given JESplex.
• The subdividing of the available tape drives into Work Groups to satisfy the requirements of different types of work, for example production versus non-production.

Functional identifier

DBS

Dependencies

DBS Application

Description of usage

DBS is designed to manage your tape drives with a minimum of intervention. Once the initial configuration definition is completed, DBS is normally transparent to both operators and users.

To manage the drives, DBS uses these resources:

• Drive Pools manage the physical devices (device numbers).
• Work Groups manage the logical segmentation of workload.

Externally, DBS requires a user-defined Configuration and Policies to determine how your installation wants to manage tape drives. These are defined with ISPF dialogs. DBS also uses ISPF to provide monitoring and display facilities.

To verify a DBS configuration

This command verifies the NEXT DBS Configuration by checking for the existence of the JES2 members, device numbers, device types, and libraries that have been defined.

The default behavior is to verify the NEXT Configuration in the ACTIVE Automation File. You can verify the Configuration in an Automation File that is not active by specifying its name:

This will evaluate the NEW Configuration if it exists, otherwise it verifies the NEXT Configuration.

To verify the ACTIVE DBS configuration

This command causes DBS to reevaluate the ACTIVE DBS Configuration against the current I/O configuration on all systems in the JESplex that are running DBS.

If your I/O configuration is changed dynamically, DBS automatically reevaluates the ACTIVE Configuration so that it can continue to manage the tape drives efficiently. Because z/OS does not provide a way to detect a dynamic reload of the Eligible Device Table (EDT), you must force a reevaluation after such an event.

To activate a DBS policy

A DBS Policy describes how to manage the resources defined in the DBS Configuration. DBS Policies can be activated through the ISPF interface or by an operator command:

This command activates a new Policy and forces DBS to e-evaluate jobs awaiting execution and apply the new Policy to them. Jobs that are already executing will finish execution even if they no longer conform to the newly Activated Policy.

For implementation and testing, you can activate a Policy in Passive mode:

This means that DBS will not hold jobs or prevent them from being selected for execution.

To remove a job from DBS control

This command removes job 5678 from DBS control. The job might still be held by JES2 or by other ThruPut Manager services.

The DBS ABANDON command applies even if the job is already running. If the job is being delayed during step initiation, the delay is removed and the step begins even if this results in allocation recovery. If a step is already running, /DBS will not manage any subsequent steps, starting with the next step to begin execution.

To change the DBS priority for a non-SLM job

You can change the DBS priority for a job provided that it is not SLM-managed:

This command instructs DBS not to delay the selection of the job, and if drive contention occurs, to give the job the highest priority. Note that this does not ensure the job will get the drive if there are other jobs with HIGH DBS priority.

To set the DBS status of DBS-managed devices

The DBS SET command allows you to control the status of devices that are managed by DBS. You can specify one or more individual devices or ranges of devices.

To display DBS status and information

This is a request for DBS status information, and results in a display similar to:

To display the DBS status of a single device defined in the DBS configuration

A typical response:

To display a range of devices

Specify the first and last device number and separate them with a hyphen (-).

To display more than one device not in a range, or to specify multiple ranges

Enclose the list in parentheses.

DBS command summary