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Discover Information :

Discover is a comprehensive, easy-to-use, disk storage management tool for HP Nonstop systems

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Discover key features include:

Powerful software for managing disk resources on HP NonStop servers

Discover provides a safe and efficient mechanism for monitoring disk resource usage on HP NonStop servers. It replaces manual methods of tracking disk and file growth, reduces the risk of human error, and frees up operations and support staff for other tasks.

Discover continuously monitors disk and file usage, and predicts potential disk full and file full conditions before they occur. You can configure Discover to automatically invoke corrective actions, or to alert an operator that manual intervention is required.

By anticipating such events, Discover helps eliminate application outages due to unforeseen disk resource problems.

In addition, Discover is work-flow oriented. It organizes "action items" which are required in order to ensure the availability of your data.

Prevention of application outages due to disk or file full conditions

Most applications depend on the availability of sufficient disk space in order to function correctly. If a disk volume becomes short of free space, an application may not be able to allocate the disk space required in order to continue running.

In addition, individual disk files may only grow to a pre-configured size. If an application continually adds new data to a file it will eventually encounter a "no space" error condition - even if there is free space available on the disk.

Either of these situations can cause part, or all, of an application to become unavailable. Discover enables you to avoid these conditions by taking corrective actions before they occur.

Continuous monitoring of disk utilization

The Discover monitor is a NonStop process pair that continually runs as a background task. At pre-defined intervals, it collects and records data on disk volume and file usage. The data is used to predict future disk and file usage, and the time at which disks and files will become full. The predictions made by Discover are also recorded so that actual and predicted usage can be compared for accuracy.

The monitor calculates expected growth over the next hour, day, week, and month. For disk files, it compares the expected growth to the configured maximum size of the file. For disk volumes, it compares the expected growth to the available space on the volume.

SpaceMaker technology for improved disk space allocation
Discover includes SpaceMaker technology which can:

Increase the amount of available free space on a disk volume
  • Typically, a disk volume contains many files that use more disk space than they actually need. When Discover detects such a file, and the file is not growing, it de-allocates the unused disk space. This makes the space available for use by other files.
Prevent extent allocation failures on growing files
  • As a file grows, it is normally allocated additional disk space as it is needed. When the file's space is all used up, the operating system allocates a new extent to contain data added to the file. The problem with this approach is that if the operating system cannot find space for a new extent, an error is returned to the application which will typically fail.

    To avoid this type of problem, Discover can pre-allocate disk space to growing files. For example, Discover can be configured to pre-allocate space a week ahead of when it is needed. When Discover predicts that a file will require more space within a week, it allocates the space ahead of time.

    There are two benefits to this approach. If the space is available, it is allocated immediately guaranteeing that the file will have enough space to accommodate the anticipated growth. If the space is not available, the system administrator will receive a warning, giving him time to take corrective measures.

File attribute monitoring

Discover keeps track of key file attributes such as the file owner, security setting, AUDIT flag, BUFFERED flag etc.. Discover detects when a file attribute is changed. You can specify which corrective measures should be taken when the condition is detected.

In addition to changes in file attributes, Discover also detects files that have been marked as broken, corrupted, or which require rollforward processing.

Automatic Reload of key sequenced files

Discover performs a health check on key sequenced files. It detects three conditions that may indicate that a key-sequenced file needs to be reloaded:

  • The number of index levels is too high
  • There is too much slack space in the file
  • The data blocks in the file are disordered
Files can be scheduled for automatic reload.

User disk space quotas

You can specify a disk space quota for the users on your system. When a user exceeds his quota, Discover performs an action specified by the system administrator. For example, a message can be logged to the console, or a report can be run listing files owned by the user.

Discover provides two reports which give details on space usage on a user by user basis. One report lists the space used, and number of files owned by a particular set of users. The other report lists all users showing those who have most exceeded their quota first.

Corrective measures initiated automatically

Discover responds automatically to the conditions that it detects. Corrective action are scheduled via the To Do List. The To Do List is like a task scheduler.

Each To Do List entry is called a task, and specifies what action is to be performed, when it is to be performed, and whether the action is manual or automatic.

Actions which may be specified include:
  • Compressing free-space on a disk volume
  • Increasing the “maxextents” value for a file
  • Reloading key-sequence files
  • Moving files to another disk volume
  • Backing up files to tape
  • Sending an alert message to the Event Management System, a log file, or a device.
  • Running a TACL script

Comprehensive reporting

The Discover command interpreter program is used to communicate with the monitor. It may be run interactively, or in batch mode. The command interpreter supports commands to generate reports from the information collected by the monitor. The available reports include:
  • Disk volumes sorted by growth rate
  • Disk volumes sorted by estimated time until full
  • Disk volumes sorted by space utilization
  • Disk volume summary showing space utilized for code files, temp files, log files etc.
  • Disk volume space usage predictions
  • Files sorted by growth rate
  • Files sorted by estimated time until full
  • File space usage predictions
  • User disk space quotas, including current use
All of these reports can produce "comma separated values" -- allowing easy importing into a spreadsheet.


Discover allows the system administrator to automate many file maintenance tasks. However, there are some situations in which full automation is not possible, or indeed, desirable.

For example, suppose the administrator wishes to clean up old files that are no longer needed. The files are to be backed up to tape and then purged from disk. He could identify "old" files as those which have not been opened for a year (as an example). However, how does he know which files are safe to purge? An application might require a certain file only on leap years, purging it would cause problems the next time it was required.

The administrator should consult the user department responsible for the files in order to confirm that it is safe to archive them. The end user may identify certain files that must be retained on disk, and others which can be purged without being backed up to tape. Armed with this feedback, the administrator can then process the files appropriately. Discover worksheets support such a change management process.

A worksheet is used to track files which the administrator has identified as candidates for some sort of action. The recommended action can be signed off by the end user, or an alternative action can be specified. When agreement is reached, the worksheet is scheduled for processing on the TODO list. Each action is performed and an optional audit trail is written to record the outcome. Files which are not signed off are not processed. They remain in the worksheet until a decision has been made on what to do with them.

Discover comes with more than ten pre-defined worksheets to handle common file maintenance tasks, for example:

  • Reloading disorganized key sequence files
  • Archiving old files
  • Increasing MAXEXTENTS for files that are becoming full
  • Purging corrupt files
  • You can add new worksheets to deal with any file maintenance tasks that you need to perform either on a one-off basis, or on a regular basis.
Files are added to a worksheet either based on conditions detected during a scan, or by the ADD FILES command.

Worksheets can be processed on demand, or automatically once a day or on specific days of the week.

Reports can be generated listing the files in a worksheet with various selection and sorting options.

Discover Utilities

Discover provides a set of useful disk utilities for use by system administrators and general users

These include:

    Checks the health of key sequenced files

    Displays information about volumes and files

    Locates the primary partition of a partitioned file

    Displays information about Saveabend files

The Recycle Bin

The recycle bin allows users to UNDELETE files that were deleted by mistake.

The DEL utility is used instead of the TACL or FUP PURGE commands. DEL deletes the file but keeps a copy in the recycle bin. the UNDEL utility restores the file from the recycle bin to its original location.

You configure the recycle bin to use a small percentage of the free space on each disk. If it fills up, the oldest files in the bin are physically purged to make way for new files. As long as a file has not been purged to make way for newer files, it can be undeleted.

There are also utilities to display information about the recycle bin, to empty it, and to repair it.


Worksheets support the BACKUP and ARCHIVE actions. These allow files to be backed up to tape (and optionally purged). The actions apply to the files in the worksheet as a group, so that the files are backed up to the same tape(s). An audit trail is kept which identifies the tape to which the files were backed up.

Easy to set up and use

Several features make Discover easy to set up and use:

  • Step by step installation procedure
  • Simple configuration parameter specification
  • Easy to use command interpreter with complete online help
  • No special system requirements
  • No SYSGEN required.

System requirements

PC: Windows 7/8/10

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Last Modified  September 2016.