• 1 reply
  • Latest Post - ‏2012-11-20T17:08:59Z by brcowan
6 Posts

Pinned topic Component VOB and PVOB restoration

‏2012-11-19T15:22:03Z |

Is it the case that in order to restore a UCM Component VOB, you must also restore the PVOB?

I ask because after a recent mishap with RMELEM I wanted our sysadmin to restore a Component VOB as no other changes had happened in that VOB. However the sysadmins advised us that we would need to restore both the Component VOB and the PVOB otherwise there would be time stamp issues between these two and the Component VOB wouldn't be useable.

Many thanks,

  • brcowan
    763 Posts

    Re: Component VOB and PVOB restoration

    As with anything else in ClearCase, the answer is a hearty "that depends..."

    If the ONLY change since the last backup of this component VOB is the rmelem, then you should be OK. If you want to be sure, you will need to do something like this:

    1) Before performing the restore, run this command and save the output:
    cleartool checkvob -ucm vob:{COMPONENT VOB tag}
    2) Remove the tag for and unregister the component VOB.
    3) RENAME the original vbs directory. (This prevents a cached registry query result from finding and opening the now-unregistered VOB)
    4) restore the component VOB to a new storage directory, leaving the previous copy UNTOUCHED.
    5) Register and tag this copy of the component VOB
    6) rerun the command in step 1, saving the output to a new file.
    7) Compare the results from #1 and #6.

    If they are identical, then you should be OK. If they are not, the odds are that you have at least one developer working within that component VOB and you will need to assess what was done and whether it is something you need to pull in from the other copy.

    Depending on the ages of the component VOBS, which versions of CC modified it over that lifetime, etc., there may be minor issues that have no operational impact reported in the checkvob -ucm output. Hence the need to run it twice and compare the results.

    Brian Cowan
    Advisory Software Engineer
    ClearCase Software Advisory Team (SWAT)
    Rational Software
    IBM Software Group
    550 King St
    Littleton, MA 01460

    Phone: 1.978.899.5436