After a virtual switch type is selected, it functions as an object that can be assigned to one or more virtual machines. Further, each virtual machine has a virtual hardware inventory in which each network adapter can be assigned a virtual switch. Virtual machines can have multiple network adapters and exist on multiple virtual switches. A number of additional features, such as bandwidth management, MAC address assignment (if an address other than the 00-15-5D-xx-xx-xx format is required), and VLAN identification, can be set as properties of the virtual machine. The virtual switch selection can be done as part of the virtual machine creation process or afterward as a task of editing the settings, as shown in Figure 6. The virtual switches are a configuration item and property of the host, to which VMs can be assigned.
Figure 6. Enabling virtual machine settings assignment of a virtual switch to the network adapter
A virtual machine can be assigned storage in a number of ways. The Virtual Fibre Channel feature of Hyper-V provides virtual machines with access to a storage network directly, such as to run a storage management tool. In most situations, a Hyper-V virtual machine running on Windows 8 uses the VHDX or VHD virtual disk format. The VHDX file is the Hyper-V virtualization format that encapsulates a hard drive for a virtual machine. Virtual machines can also access a pass-through disk, which is a physical hard drive on the computer running Windows 8 with the Hyper-V feature enabled that a virtual machine uses exclusively. The pass-through configuration is not very transportable or scalable, so in most situations, VHDX and VHD virtual disk files are recommended.
Each Hyper-V virtual machine can have virtualized I/O controllers to provide storage resources (Figure 7), including IDE and SCSI controllers. Both these controllers can provide virtual disks in the VHDX or VHD format, and the virtual IDE controller can provide a virtualized optical drive for CD/DVD ISO files. Like the physical IDE and SCSI controllers in computers, these virtualized controllers have addresses. For example, the IDE controllers can provide a virtual machine with individual VHDX or VHD files on IDE Controller 0 and IDE Controller 1 and, within that, on address 0 or 1. This is much like a physical controller in many PCs. The Hyper-V virtual SCSI controller can address positions from SCSI ID 0 up to 63 and assign devices to virtual machines. Individual Hyper-V virtual machines can have both virtual IDE and SCSI controllers and can have multiple controllers. The virtual switches are a configuration item and property of the host, to which virtual machines can be assigned.
REAL WORLD: UNDERSTAND THIS ABILITY BUT DON’T WORRY TOO MUCH ABOUT IT
Most Windows administrators don’t need to change the IDE or SCSI addressing, but you can adjust this property of the individual virtual machine if needed. Changing this can affect the start order of the virtual machine, so proceed carefully if you add VHDX or VHD files to a virtual machine.
Figure 7. Virtual IDE and SCSI for each virtual machine
The VHDX and VHD files associated with a VM have to reside on a disk resource that the Windows 8–based computer with the Hyper-V feature enabled can access. This can be fixed local disk resources (SATA, USB, Thunderbolt, and so on), a network resource with the new SMB 3.0 support from Windows Server 2012, or Windows Server 8 as a block storage resource. The block storage resource can be an iSCSI target formatted as an NTFS file system and assigned directly to the computer running Windows 8 with the Hyper-V feature enabled. A Fibre Channel logical unit number (LUN) can also be deployed to a computer running Windows 8 and formatted. This is different from the Virtual Fibre Channel technology that can place a virtual machine on the storage network in that the LUN would be assigned to the Windows 8–based computer with the Hyper-V feature enabled and then formatted as NTFS. After the iSCSI or Fibre Channel LUNs are formatted, virtual machines can reside on these storage resources.
WINDOWS 8 STORAGE SHOULD BE SIMPLE
Although Windows 8 with the Hyper-V feature enabled has the same rich storage options as Hyper-V on Windows Server 2012, virtual machines running on local storage and removable media are a popular choice for most Windows 8 users. If SAN storage infrastructures are deployed, consider using the free Hyper-V hypervisor, Hyper-V Server 2012. This is much like a core installation of Windows Server with the Hyper-V role, but it is free.
