Turnkey Virtual Storage Support

With the September 2019 BRMS PTFs: 7.2 SI70624, 7.3 SI70625, and 7.4 SI70626, BRMS has been enhanced to provide automatic backups to virtual tape and virtual optical devices. With this enhancement, BRMS automatically will create virtual devices and virtual media to perform a backup once BRMS maintenance (STRMNTBRM) or INZBRM *DATA has been run. To enable this feature, BRMS creates default media classes named QAVVRTTAP with a default density of *VRT256K for tape and QAVVRTOPT with a default density of *VRTUDF for optical. Assigning one of these media classes to a media policy and using the device parameter of *MEDCLS will enable turnkey virtual backups.

Example: how to set up automatic backups to virtual storage

Create a media policy to use the BRMS created media class named QAVVRTTAP.

  1. In the command line, enter WRKPCYBRM *MED to open the Work with Media Policies screen.
  2. Chose option 1, Create and name the media policy AUTOVRT. Press Enter to open the Create Media Policy screen.
  3. In the Media class field, set the media class value to QAVVRTTAP. Press Enter.
  4. The system returns a Policy AUTOVRT created message.

A new media policy, AUTOVRT with media class QAVVRTTAP is available for use.

Example: running a Save Library using BRM (SAVLIBBRM) command using the AUTOVRT media policy

If there are five individual libraries that a user wants to save to virtual media (LIB01 LIB02 LIB03 LIB04 LIB05), the new AUTOVRT media policy and the associated media class can do this with one SAVLIBBRM command on the selected libraries.

When running the command: SAVLIBBRM LIB(LIB01 LIB02 LIB03 LIB04 LIB05) DEV(*MEDCLS) MEDPCY(AUTOVRT)

BRMS automatically creates a virtual device and an image catalog with image entries and adds the media into the BRMS media inventory and performs the backup on the libraries.

Creating a backup control group using the AUTOVRT media policy.

Users can create a backup control group by selecting backup items and doing one of the following:

  • Set the Media policy to AUTOVRT and set the Backup devices to *MEDCLS on the Work with Backup Control Groups (WRKCTLGBRM *BKU) display with option 8, Change attributes.
  • Use DEV(*MEDCLS) MEDCLS(AUTOVRT) on the STRBKUBRM command.

BRMS automatically will create a virtual device and an image catalog with an image entry and will add the media into the BRMS media inventory and will perform the backup.


Considerations:

Here are some items to consider when using BRMS virtual storage support:

  1. Size.
    • BRMS will default to create virtual media with a size of 30G.
    • The media size can be overridden by running the following command: CALL PGM(QBRM/Q1AOLD) PARM('VRTVOLSIZE' '*SET ' 'nnnnnnn') where - nnnnnnn is the media size in megabytes (MB). This value must be between 0000001 (1 megabyte (MB)) and 1000000 (1 terabyte (TB)). NOTE: The size maybe adjusted slightly to reflect minimum or maximum size of the virtual media.
    • The media size can be displayed by running the following command: CALL PGM(QBRM/Q1AOLD) PARM('VRTVOLSIZE' '*DISPLAY').
    • The media size can be reset to the default value by running the following command: CALL PGM(QBRM/Q1AOLD) PARM('VRTVOLSIZE' '*REMOVE').
    • Additional notes regarding size:
      1. When virtual tape media is created, the image size allocated is the amount of storage required to initialize the image.
      2. When virtual optical media is created, the image size will allocate the full volume size in the image catalog directory.
      3. Using virtual media requires a large amount of system storage. Symptoms that indicates your system storage is too small include:
        • BRM1799 message indicating the save operation was cancelled.
      4. Larger size tape volumes will improve BRMS operational efficiency. To optimize BRMS, ensure that the volume sizes use enough storage:
        • The BRM4123 message also may not list all volumes.
        • The backup fails with message RNQ0121 or MCH0603.
           
  2. BRMS will default to create virtual media using *SYSBAS storage for virtual media. The default can be overridden to create virtual image catalog entries for backups on an ASP or IASP instead of using *SYSBAS space.
    • The ASP for BRMS to use can be specified by running the following command: CALL PGM(QBRM/Q1AOLD) PARM('CLDTRFASP ' '*SET ' 'nnnnnnnnnn') where - nnnnnnnnnn is the ASP name.
    • The ASP value can be displayed by running the following command: CALL PGM(QBRM/Q1AOLD) PARM('CLDTRFASP ' '*DISPLAY').
    • The ASP value can be reset to the default value of *SYSTEM by running the following command: CALL PGM(QBRM/Q1AOLD) PARM('CLDTRFASP ' '*REMOVE').
       
  3. When using the QAVVRTOPT media class the BRMS default is to create 10 virtual media for the backup.
    • The number of virtual optical volumes to create can be specified by running the following command: CALL PGM(QBRM/Q1AOLD) PARM('NUMOPTVOLS' '*SET ' 'nn') where - nn is the number of volumes to auto create. This value must be between 01 and 75.
    • The number of volumes to create can be displayed by running the following command: CALL PGM(QBRM/Q1AOLD) PARM('NUMOPTVOLS' '*DISPLAY').
    • The media size can be reset to the default value of 10 by running the following command: CALL PGM(QBRM/Q1AOLD) PARM('NUMOPTVOLS' '*REMOVE').
      • Since optical devices do not have an exit program interface to handle media switching while a backup is running, the backup command must provide enough volumes to successfully hold the backup. A symptom that indicates the backup does not fit on the initial number of volumes provided is the backup will fail with message BRM4301 'Volume list exhausted'.
         
  4. Users should not remove media named in the form Qxxxxx from the BRMS inventory that are in BRMS managed image catalog Q1ABRMPOOL or an image catalog named in the form Q1ACQxxxxx as this media is managed internally by BRMS.
    • After media named in the form Qxxxxx is expired, BRMS maintenance should be ran to clean up the image catalog space and BRMS inventory. Maintenance will delete the image entry from the image catalog and delete the volume from the BRMS inventory. If the image entry being deleted is the last entry in the image catalog, the image catalog will also be deleted.
    • Q1ABRMPOOL virtual images use the ASP storage that is set when the image catalog is initially created.  The storage used does not change when using CALL PGM(QBRM/Q1AOLD) PARM('CLDTRFASP ' '*SET ' 'nnnnnnnnnn') where - nnnnnnnnnn is the ASP name if the image catalog already exists.  To change the ASP storage used, the image catalog and images need to be removed and the media needs to be expired and removed from the BRMS inventory before changing the ASP storage setting.
       
  5. Backups using media class QAVVRTTAP and QAVVRTOPT will always write to sequence 1, appending is not supported.
     
  6. BRMS will select virtual devices by alphabetical order and load them to the proper image catalog. The device will be unloaded and varied off when the BRMS operation completes.
     
  7. DUPMEDBRM operation from your virtual tape to a physical drive is recommended if a full system save was done or critical data resides on your virtual volumes. The DUPMEDBRM needs to Save media information (SAVMEDINF) if the duplication to physical is needed for disaster recovery.
     
  8. Full system backups using virtual devices and image catalogs are not intended to be used by BRMS as a disaster recovery solution because the virtual media storage is not saved.