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.
What this means:
- You can use storage vMotion to migrate both the virtual disks and VM configuration file while the recovery VM is running without the VM crashing.
- You can make the destination disk thin-provisioned in order to minimize recovery time.
This is important because it is currently the only method for migrating a running ESXi Virtualization as thin-provisioned to a permanent datastore which is necessary in order to meet certain RTOs.
To migrate the datastore of an ESXi Virtualization to Storage vMotion, follow these steps:
- Start ESXi VM restore from the Datto.
- 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.
- 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.
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 just fine, however the RDM mapped VMDKs are equivalent to symlinks so, 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. Therefore to avoid those issues:
- use NFS offload
- when using iSCSI, change destination format in vMotion dialog, to not be "Same as source"
- Migration with Storage vMotion (external link)