Quick storage migration (QSM) provides the ability to transfer a virtual machine (VM)'s storage from one location to another. The VM is available during a majority of the transfer process; however, there is a gap of VM availability at the tail end of the process. QSM can occur within a single host. QSM can occur from a host or cluster to another host or cluster.
Within a single host: To move from a traditional volume to a Cluster Shared Volume (CSV)—after completing an upgrade from R1 to R2 To move from a local disk to shared storage To move between shared storage devicesAcross hosts/clusters:In addition to single host use cases, these use cases are applicable: To migrate a VM between two hosts that are not within the same cluster To migration a VM across clusters Note: Moving across hosts/clusters can be extremely useful when moving from a test to production environment if there is at least one shared network between the two environments and Microsoft® Service Center Virtual Machine Manager (SCVMM) suite has access to that shared network.
Note: Moving across hosts/clusters can be extremely useful when moving from a test to production environment if there is at least one shared network between the two environments and Microsoft® Service Center Virtual Machine Manager (SCVMM) suite has access to that shared network.
The following steps provide an overview of the migration process: A QSM is requested through SCVMM R2 between two hosts/clusters or within the same host. A snapshot of the VHD(s) is created (also referred to as checkpoints in SCVMM). This process creates a differencing chain leaving a base VHD that is a point-in-time snapshot of the VHD and a differencing VHD that contains any changes made to the virtual disk post-snapshot. The base VHD(s) is copied over the network through BITS (secure copy) to the target location. The VM is placed in a saved state (similar to what occurs with a VM quick migration). The VM is offline at this point. The differencing disk and VM state/configuration files are copied through BITS to the target system. On the target system, the snapshots are merged to restore the original structure and the original source VM is removed. The VM is resumed on the target system.
The following must be in place to support QSM: SCVMM 2008 R2 Hosts running Hyper-V R2 Processor compatibility between source and target systems (in line with requirements for VM quick/live migration) All VM storage resides on VHDs Space exists on the source and target volumes to support all VM files including the differencing disk that is created during the QSM process. For more information on this requirement refer to this blog: http://joeelway.spaces.live.com/blog/cns!2095EAC3772C41DB!2538.entry