Topic
2 replies Latest Post - ‏2013-02-06T10:35:53Z by SystemAdmin
janfrode
janfrode
17 Posts
ACCEPTED ANSWER

Pinned topic Storwize v7000 global mirror with change volume

‏2013-01-08T11:12:05Z |
Could someone please confirm that what we're seeing is the expected behaviour when using Global Mirror with Change volume ?

On site 1 I have Vol1 in the "performance pool", and change volume Vol1-change in the "capacity pool". This is mirrored to site 2 with Vol1-site2 in the "capacity pool" and Vol1-change-site2 also in the "capacity pool" on site 2

In my "Running task" view I always see this remote copy operation listed as running with progress bar at 99%. Should it always be at 99%?

In copy-services -- FlashCopy Mappings I see

fcmap0 Vol1 -> Vol1-change with status "Stopped", progress 0%.
fcmap3 Vol1-change -> Vol1 with status "Idle", progress 0%.

This mapping from vol1-change tol vol1 looks very strange to me. Why is it mapping back to vol1?

It seems every now and then that the flash-copy for fcmap0 changes from "Stopped" to "Copying". Are there any logs I can monitor to see that how long it's taking for doing each snapshot + data mirroring to site2?

Also, our change volume has gotten quite big (500GB used, out of 2 TB volume). Is there an easy procedure for reducing this to a smaller size once we know that the cyclic changes should be much smaller ?
Updated on 2013-02-06T10:35:53Z at 2013-02-06T10:35:53Z by SystemAdmin
  • SystemAdmin
    SystemAdmin
    4779 Posts
    ACCEPTED ANSWER

    Re: Storwize v7000 global mirror with change volume

    ‏2013-01-28T11:24:05Z  in response to janfrode
    I'm glad you posted this as I was also searching for the mystery around the task constantly running at 99%.

    Interestingly when I first setup the Global Mirror with CV I didn't have the task and my consistency group was showing "Consistent Copying". I decided to test a switch over on the volumes to confirm the data was OK (which it was!) but since switching back I now have this task running?! The fact that the consistency group is still showing "Consistent Copying" would suggest this is normal but I cannot find any official documentation to confirm this?

    I can confirm your FC mappings match mine.

    Can anyone shed any light on this, is this by design? If so why did I not have this task on initial setup?

    Thanks in advance.
    • SystemAdmin
      SystemAdmin
      4779 Posts
      ACCEPTED ANSWER

      Re: Storwize v7000 global mirror with change volume

      ‏2013-02-06T10:35:53Z  in response to SystemAdmin
      After speaking to an IBM install engineer today I can confirm that having a constant Remote Copy operation for change volumes is completely normal.

      He couldn't explain why it wasn't there at first, but I'm just happy to know that it is functioning as expected!