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Shadowing and Shadow Copies?

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The Question is:

I am having trouble replacing a defective disk within a shadow set. When I shut
 down my VAX and install another disk (same size, etc...) the systartup get to
 the point where it mounts the shadow set and then repeats that it is doing a
 copy operation over
and over again. I waited almost 2 hours and that is all it does. The system
 never completes the copy operation and I can't login to the console.
As I can't leave it doing this for more than 2 hour, is there some way I can
 have VMS do the synchronization while completing the VMS boot?
What exactly is the procedure for replacing a bad disk from a shadow set?
Thank you

The Answer is :

    It is unclear from your statement what the actual problem is.
    Copy operations are done "in the background" by the SHADOW_SERVER
    process, and should not prevent the mount from succeeding nor
    the command procedure from continuing.
    In general, Host-Based Volume Shadowing (HBVS) copy operations
    do not interfere with access to a shadow set, while HBVS merge
    operations can have a marked negative impact on performance
    (note that the recently-released Host-Based Minimerge
    for OpenVMS Alpha for V7.3-2 can help out here.)  But I digress . . .
    A simple approach would be to modify your startup commmand procedure
    so as not to mount the shadow set as a multi-member device, but as a
    single-member shadow set, using only the good member, of course.
    Once the system has booted, you can add the new disk with the
    MOUNT command.
    Please verify that the system parameter SHADOW_MAX_COPY is non-zero,
    or the copy won't start on this system.

answer written or last revised on ( 8-SEP-2004 )

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