Hyper-V allows virtual machines to access storage mapped directly to the Hyper-V server without requiring the volume be configured. The storage can either be a physical disk internal to the Hyper-V server or it can be a Storage Area Network (SAN) Logical Unit (LUN) mapped to the Hyper-V server. To ensure the Guest has exclusive access to the storage, it must be placed in an Offline state from the Hyper-V server perspective. Additionally, this raw piece of storage is not limited in size so, hypothetically, it can be a multi-terabyte LUN.

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