Adding volumes to SMS-managed database files in Datacom
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Adding volumes to SMS-managed database files in Datacom


Article ID: 33629


Updated On:


Datacom/DB Datacom Datacom/AD


A  Datacom database index or data file is managed the same as any other standard sequential Basic-type file in z/OS.

This article explains how to add more volumes to an SMS-managed file. Due to the size of a particular file, it may not be possible to perform a standard process to backup, allocate, initialize and load a new file; therefore, this procedure is a good alternative.



Release : 15.1

Component : Datacom/AD

Component : Datacom/DB



This process can be done with minimal disruption to an application; however, for best effect, it should be done during a period of light activity for the database area.

  1. Identify the file name, if needed, from a CXX report;
  2. Be sure that the SMS storage group has enough volumes;
  3. If the file was defined using a specific SMS Data class, be sure that the volume limit in that class is sufficient to contain these new volumes;
  4. Determine how many volumes you want to add to the candidate list for this file;
  5. Run an IDCAMS LISTCAT report or your own utility before the change to identify the list of volumes before the change;
  6. Run IDCAMS (or use a TSO command) to change the catalog definition for the file to add the new volumes. For example, if adding 4 volumes to the definition, you would use the command:
    ALTER dsn AVOL(* * * *)
    Note: The number of asterisks in this command reflects the number of new volumes being added;
  7. Run a LISTCAT report or your own utility after the above command to ensure the file is now defined correctly.
  8. Close the database in CICS regions if needed with DBOC CLOSE=nnn and then close the database in the MUF using a DBUTLTY COMM CLOSE,DBID=nnn command. With the next request to the database, the file will be automatically opened, and it will retrieve the attributes from the system catalog – including the updated volume candidate list. Then, if the database needs to be extended by a manual or dynamic extend process, the new volumes will be used as defined. To reopen the DBID in CICS use DBOC OPEN=nnn

Additional Information

For more information on the IDCAMS ALTER ADDVOLUME command, please refer to the IBM z/OS DFSMS Access Method Services Commands documentation for the ALTER command

As always, please contact Broadcom support for Datacom if you have further questions.