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ClearCase Support: How to Duplicate a VOB


Here are the procedures to move or duplicate a ClearCase UNIX VOB from one VOB server to another VOB server. If the VOB server is not changing, then the VOB can be moved instead, but these procedures will work too.
  1. Determine the VOB's current location and the VOB server that hosts the VOB by using this command.

    cleartool describe [-long] vob:VOB_TAG
  2. Determine the VOB's size by using this command.

    cleartool space VOB_TAG
  3. Determine the server and location that the VOB is being moved to and if the VOB has sufficient disk space in the new location by using this command. You may need the remote ClearCase administrator to do this step.

    df –k NEW_VOB_PARTITION
  4. Schedule a VOB shutdown. Wait until the start of the shutdown period before continuing these procedures.
  5. Verify that the VOB was recently and successfully backed up as a precaution.
  6. Log into the VOB's server as root.

    rlogin SERVER_NAME -l root
  7. Lock the VOB.

    cleartool lock vob:VOB_TAG
  8. Dump the VOB. Dumping the VOB may take a very long time depending on the size of the VOB. You can skip this step if you are duplicating the VOB to a server with the identical OS version and ClearCase version. Otherwise, dumping the VOB requires a temporary disk space to store an extra copy of the entire VOB. If you do not have enough disk space, you can use the "-to" argument to reference a temporary location.

    cleartool reformatvob -dump [-to DUMP_DIRECTORY] VOB_STORAGE_DIRECTORY

  9. When this command finishes, you will find two files or directories called "db.reformat" and “dump.done" in the VOB's storage directory or dump directory. If these files do not exist, then the dump was not successful.

  10. Compress the dumped VOB data for easy transport.

    cd VOB_PARTITION
    tar –cf - ./VOB_STORAGE_DIRECTORY | /usr/atria/etc/Gzip > TEMP_DIRECTORY/VOB_NAME.tar.gz


    If you created the "dump.done" file in another directory, then you will need to compress this data too.

    cd DUMP_DIRECTORY
    tar –cf - ./DUMP_SUB_DIRECTORY | /usr/atria/etc/Gzip > TEMP_DIRECTORY/VOB_NAME_dump.tar.gz

  11. Re-load or restore the VOB Database back to normal. This command should unlock the VOB too. Skip this step if you skipped the dumping of the VOB because you are duplicating the VOB to a server with the identical OS version and ClearCase version. If you do skip this step, then you must manually unlock this VOB with the command: "cleartool unlock vob:VOB_TAG". Otherwise, load the VOB with this command.

    cleartool reformatvob -load VOB_STORAGE_DIRECTORY

  12. When done, this will create a temporary DB file with the name "db.TIME_STAMP", such as "db.10.16". Verify this file exists in the VOB_STORAGE_DIRECTORY. You may delete this file after verifying the VOB is working again, but I recommend waiting a few days before deleting it.

  13. Test that the VOB is working again.
  14. Transfer the dumped and compressed files via fship or ftp. Ask the other ClearCase administrator what machine and how to transfer it.

  15. Notify the other ClearCase administrator that the duplicated VOB was shipped.




At this point, the other ClearCase administrator (who could be you) will have to import this duplicated or dumped VOB onto their VOB server. They can follow these procedures.
  1. Log into the VOB's server as root.

    rlogin SERVER_NAME -l root
  2. Go to the VOB partition that will host the VOB.

    cd VOB_PARTITION

  3. Uncompress the VOB data files.

    /usr/atria/etc/Gzip –d TEMP_DIRECTORY/VOB_NAME.tar.gz
    tar –xf VOB_NAME.tar

  4. Load the VOB Database.

    cleartool reformatvob –load VOB_STORAGE_PATH
  5. Delete the temporary timestamp database.

    rm –rf VOB_STORAGE_PATH/db.TIME_STAMP
  6. Register the VOB on the UNIX Region with this command.

    cleartool reg –vob –host HOST_NAME VOB_STORAGE_PATH VOB_STORAGE_PATH
  7. Create the VOB's UNIX tag.

    cleartool mktag –vob –tag VOB_TAG [-public] -password REGISTRY_PASSWORD -host HOST_NAME –hpath VOB_STORAGE_PATH VOB_STORAGE_PATH
  8. Mount the VOB on all UNIX servers.

    cleartool mount VOB_TAG
  9. Use the Windows Region Synchronizer to make the VOB available on Windows, and mount the VOB on any Windows servers too.
  10. Test the VOB, change the VOB's permissions to the required local configuration, and install all required triggers.
  11. Skip this step if the VOB is not MultiSited or synchronized with another VOB replica. Have the master replica of VOB change the host name of the moved VOB replica with this command.

    multitool chreplica -nc -host NEW_HOST_NAME replica:REPLICA_NAME@vob:VOB_TAG
  12. Inform all users that the VOB is online and ready to be used.
  13. After several days or weeks with the duplicated VOB in use and with no problems, you can delete the compressed files.

You are done duplicating the VOB.

by Phil for Humanity
on 20081016

Related Articles
 » ClearCase Support: How to Move a VOB
 » ClearCase Support: How to Reformat or Defragment a ClearCase VOB
 » ClearCase Support: How to Backup a VOB