Configure EMC VNX Synchronous Snapshots

setting the <partition>.storage.enablesyncsnaps property to true will cause snapshots to be set synchronously during a euca-create-snapshot operation. In this mode, the snapshot is created synchronously before the euca-create-snapshot command returns, while the copy and upload to Walrus still takes place asynchronously. This helps ensure that the euca-create-snapshot command returns quickly.

If the CLC loses the connection with the SC or if the connection times out (the default timeout is 60 seconds), the SC will detect the connection has been closed and will mark the snapshot as failed and will clean up. This detection occurs after the VNX snapshot has been created, but before it initiates the thread that performs the asynchronous migration and transfer of the snapshot LUN to Walrus. When using synchronous snapshot mode, if the CLC returns an error to the user on the euca-create-snapshot command then the snapshot will be marked as failed when listing snapshots using the euca-describe-snapshots command.

To configure synchronous snapshots for an EMC VNX SAN:

1. Set the <partition>.storage.enablesyncsnaps property to true :

    euca-modify-property -p mypartition.storage.enablesyncsnaps=true

You have now successfully configured synchronous snapshots for your EMC VNX SAN installation.