How to storage vMotion a Datto-managed ESX virtualization

Topic

ESXi virtualizations are compatible with storage vMotion. You can use this vSphere feature to migrate the storage and configuration files for running recovery VMs to a new permanent datastore of choice in a vSphere environment.

NOTE  This feature requires ESXi version 5.5 or newer and a suitable vSphere Standard/Enterprise (Plus) license.

Environment

  • Datto SIRIS
  • Datto ALTO

Description

What is vMotion?

vMotion is a feature of VMware vSphere, which allows live migration of virtual machines (VMs) between physical servers without downtime.

  • Storage vMotion can be used to migrate both the virtual disks and VM configuration file while the recovery VM is running without the VM crashing.
  • The destination disk can be made as thin-provisioned, in order to minimize recovery time.
  • vMotion is currently the only method for migrating a running ESXi Virtualization as thin-provisioned to a permanent datastore, which may be necessary to meet certain RTOs.

Process

To migrate the datastore of an ESXi Virtualization using Storage vMotion, follow these steps:

  1. Start ESXi VM restore from the Datto.

  2. Log in to ESXi client on VMware, and kick off Storage vMotion.

    • When iSCSI offloading is used, change the destination file format to be anything other than "Same as Source." This will make ESXi actually move the data, not just the RDM links. See iSCSI notes below.

  3. Stop and remove the Restore from the Datto.

    • Stop VM does not stop the migrated VM.

    • Stop and Unmount - removes restore entries from the Datto, but the migrated VM is still up and running.

    If any unexpected behavior is uncovered after performing the migration with VMotion, please contact Support for further assistance.

Notes for iSCSI

The way iSCSI offload is done is via RDM mapped drives. This means that when vMotioning such disks, ESXi will move RDM mapped VMDK, however the RDM mapped VMDKs are equivalent to symlinks. What is being moved between datastores are the symlinks, not the underlying data... "Unmounting" such migrated VM from Device will cause the migrated VM to crash as it still points to the iSCSI LUN that will no longer be accessible. To avoid those issues:

  1. Use NFS offload.

  2. When using iSCSI, change destination format in vMotion dialog, to not be "Same as source".

Additional Resources