Visit Open-E website
Results 1 to 6 of 6

Thread: NAS, Volume Replication. How to switch source-destination?

  1. #1

    Default NAS, Volume Replication. How to switch source-destination?

    Hi!
    I have two identical DSSes (64-bit 3518).
    I enabled Volume replication on the NAS volume according to the Open-E Volume Replication IG
    Replication task is running, share is available on the Primary DSS, Secondary is in the Destination mode and share is not available there.

    Now what are the proper switch-over and switch-back procedures?

    I had to completely remove replication task on the Secondary and modify the volume to make it source and "clean metadata" to make the share available.
    But in this case I think I have to completely synchronize entire volume from Secondary to Primary when Primary is back. Then re-point users to Primary and do a full sync from Primary to Secondary once again?
    Hope I'm wrong here and there is a less bandwidth-consuming procedure...

    Thanks for you help.

  2. #2

    Default

    hey tim

    That sounds correct. the destination volume will not be available with volume replication.
    It works in block mode.

  3. #3

    Default

    Right, and this (the fact that in destination mode NAS volume is invisible) was mentioned in how-to guides and on forum.

    My question is regarding switchover procedure -- is it the only way to completely remove replication and set it up in opposite direction, as I said in my first post?

    I looked through how-to's and found no clear answer...

  4. #4

    Default

    When switching over you have to stop the running task then as per the instructions from the online help manual to clear the metadata and set to source. Make sure to set the old source to destination.

    Clearing metadata is required when you want to start the replication process from the beginning. Another usage example is when the data on the source volume is inconsistent and you want to restore it from the destination volume. In this situation you need to switch replication modes between the volumes (i.e. the destination volume should now be in source mode, while the previous source should be switched to destination mode). Before starting a replication for a new source and destination please clear the metadata from the previous destination volume. When replication is complete the data on the previous source volume will be consistent. If a volume is set to the destination replication mode then it will not be visible in the iSCSI initiator.
    Note
    In case the problems occur while switching replication mode please tick both boxes (mode choosing and clear metadata) at the same time.
    All the best,

    Todd Maxwell


    Follow the red "E"
    Facebook | Twitter | YouTube

  5. #5

    Default

    Thanks, Todd,

    I assume that cleaning metadata means copying all data from the Source to Destination.
    And if took offline my Primary DSS (say for hardware maintenance) I will have to make it Destination, then "Clear metadata" on it to force full replication from Secondary to Primary and when the volume is in consistent state, make Secondary a Destination and make Primary a Source and "clean metadata" again for full replication from Primary Source to Secondary Destination once more.

    Am I right here or I may skip "clear metadata" somewhere?

    Also, when should I clear metadata on Source volume and when on Destination? Or it does not matter and will force full replication anyway?

  6. #6

    Default

    Metadata is pointers and information of the data and replication info.

    Just do this for the destination server. Other information below about switching over.

    http://kb.open-e.com/entry/15/

    http://kb.open-e.com/entry/147/
    All the best,

    Todd Maxwell


    Follow the red "E"
    Facebook | Twitter | YouTube

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •