A. Live Migration is the technology that copies the memory of a virtual machine (VM) between nodes in a cluster while the VM is still running, but that's just one part of the migration. The other part is moving the storage of the VM (the virtual hard disks) between nodes.
CSV allows the LUNs on shared storage to be seen by all nodes in the cluster at the same time, so there's no delay associated with dismounting the LUN on one node and mounting it on another. If you're not using CSV, then as part of the migration the LUN will have to be dismounted and then mounted on the new node. This operation will take several seconds and cause a longer interruption to communication to the VM.
Because of this, it's quite normal to see longer Live Migration times if you don't use CSV than if you do.
Related Reading:
- Q. Should I disable NetBIOS over TCP/IP on my Windows Server 2008 R2 Cluster Shared Volume (CSV) cluster networks?
- Q. How do I manually and cleanly perform a disk defragmentation or use Chkdsk on a Cluster Shared Volume (CSV)?
- Q. Do any third party disk defragmentation tools support Cluster Shared Volumes (CSVs)?
- Q. Can a Hyper-V guest use pass-through disks and still use Live Migration?
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