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VAX Hardware Virtualization allows users of HP VAX computers to move application software and user data to a non-VAX platform without having to make changes to software and data. VAX Hardware Virtualization is a software solution that replaces VAX hardware.
This approach is best understood when the VAX Hardware Virtualization Software is viewed as a special interface between the old VAX software and a new hardware platform. Basically, the CHARON software presents a VAX hardware interface to the original VAX 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 or 32-bit Intel or AMD) and continue to run for many more years.
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The Virtualization Software presents standard VAX devices to the VAX operating system, allowing the OS to function as though it were still running on a VAX computer. For example, virtual disk container files in a directory or device files in /dev directory of the host Linux platform are presented by the Virtualization Software to the VAX OS as emulated SCSI disks attached to a 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.
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