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HP Alpha Hardware Virtualization allows users of HP Alpha (Previously known as DIGITAL Alpha) computers to move application software and user data to a modern Intel or AMD based x64 compatible platform without having to make changes to software and data. HP Alpha Hardware Virtualization is a software solution that replaces HP Alpha hardware.
This approach is best understood when the HP Alpha Hardware Virtualization Software is viewed as a special interface between the old HP Alpha software and a new hardware platform. Basically, the CHARON software presents a HP Alpha hardware interface to the original HP Alpha software, so that the existing software cannot detect a difference. This means no changes have to be made to the existing software. User programs and data can be copied to a new modern industry standard server (64-bit Intel or AMD) and continue to run for many more years.
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The Virtualization Software presents standard HP Alpha devices to the HP Alpha operating system, allowing the OS to function as though it were still running on a HP Alpha computer. For example, virtual disk container files in a directory or physical devices of the host Windows platform are presented by the Virtualization Software to the HP Alpha OS as emulated SCSI disks attached to a PCI SCSI adapter.
With the use of current storage technology, disks do not have to be physically attached to the Host platform, they can also reside on a SAN or iSCSI storage structure. A similar translation process is also valid for other emulated hardware devices.
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