Patent ID: 6845466

Claim:
A method of operating a computer entity comprising a plurality of data storage devices, to install at least one said data storage device, said method comprising the steps of: checking a first said data storage device for a digital signature; checking a second said data storage device for a digital signature; determining whether said first and second digital signatures match each other; if a discrepancy in signatures is found between said first and second data storage devices, setting digital signatures of said first and second data storage devices to be in a self consistent set; and re-setting said computer entity to a known state, wherein if: said first data storage device contains an operating system, and a digital signature is found on said first data storage device; and no digital signature is found on said second data storage device; then said step of re-setting said computer entity to a known operational state comprises: re-building a primary operating system on said first data storage device; and deleting data from said second data storage device.