 |
|
Content Owner: Roman Macek | ||||
Summary
.vhdx (incl. sharing and online resizing - NEW), vhd, pass-through (raw)
Details
Hyper-V in Server 2012 introduced an updated virtual disk format: VHDX. Pass-through (raw) disks and .VHD disks are also supported. You can convert a .vhd file to .vhd using Hyper-V Manager or VMM.
Server 2012 R2 added support for virtual hard disk resizing while the vm is running (only available for VHDX files that are attached to a SCSI controller). Additionally it enables clustering virtual machines by using shared virtual hard disk (VHDX) files.
In WIndows Server 2016, Microsoft has improved the shared VHDX (VHD Set). You can now online resize the disk, move it and backup it from the host level. The improvment is called VHD Set.
Use vhdx whenever possible - the only likely reason why not to use vhd is in case you expect to move the vm to an (older) host with a Hyper-V version not supporting vhdx.
The main VHDX features are:
- Support for virtual storage of up to 64 TB
- Protection against data corruption (logging updates to VHDX metadata)
- Improved alignment of the virtual hard disk format to work well on large sector physical disks.
Other:
- Larger block sizes for dynamic and differential disks (allowing these disks to attune to the needs of the workload)
- 4-KB logical sector virtual disk that allows for increased performance when used by applications and workloads that are designed for 4-KB sectors.
- Ability to store custom metadata about the file (e.g. OS version, or updates that have been applied)
- trim - resulting in smaller files size and allowing the underlying physical storage device to reclaim unused space. (Trim requires direct-attached storage or SCSI disks and trim-compatible hardware.)
Server 2012 R2 added support for virtual hard disk resizing while the vm is running (only available for VHDX files that are attached to a SCSI controller). Additionally it enables clustering virtual machines by using shared virtual hard disk (VHDX) files.
In WIndows Server 2016, Microsoft has improved the shared VHDX (VHD Set). You can now online resize the disk, move it and backup it from the host level. The improvment is called VHD Set.
Use vhdx whenever possible - the only likely reason why not to use vhd is in case you expect to move the vm to an (older) host with a Hyper-V version not supporting vhdx.
The main VHDX features are:
- Support for virtual storage of up to 64 TB
- Protection against data corruption (logging updates to VHDX metadata)
- Improved alignment of the virtual hard disk format to work well on large sector physical disks.
Other:
- Larger block sizes for dynamic and differential disks (allowing these disks to attune to the needs of the workload)
- 4-KB logical sector virtual disk that allows for increased performance when used by applications and workloads that are designed for 4-KB sectors.
- Ability to store custom metadata about the file (e.g. OS version, or updates that have been applied)
- trim - resulting in smaller files size and allowing the underlying physical storage device to reclaim unused space. (Trim requires direct-attached storage or SCSI disks and trim-compatible hardware.)
