12.5.3. Overview of Live Storage Migration

Virtual machine disks can be migrated from one storage domain to another while the virtual machine to which they are attached is running. This is referred to as live storage migration. When a disk attached to a running virtual machine is migrated, a snapshot of that disk's image chain is created in the source storage domain, and the entire image chain is replicated in the destination storage domain. As such, ensure that you have sufficient storage space in both the source storage domain and the destination storage domain to host both the disk image chain and the snapshot. A new snapshot is created on each live storage migration attempt, even when the migration fails.

Important

To remove the live storage migration snapshot, you must manually delete it while the virtual machine is shut down. For detailed information on snapshot deletion, see the Snapshot Deletion section of the Red Hat Enterprise Virtualization Technical Guide.
Consider the following when using live storage migration:
  • Live storage migration creates a snapshot.
  • You can live migrate multiple disks at one time.
  • Multiple disks for the same virtual machine can reside across more than one storage domain, but the image chain for each disk must reside on a single storage domain.
  • You can live migrate disks only between two file-based domains (NFS, POSIX, and GlusterFS) or between two block-based domains (FCP and iSCSI).
  • You cannot live migrate direct LUN hard disk images or disks marked as shareable.
Report a bug