Boot Image Control - Boot Turns and Re-imaging

Boot Turns and Re-imaging

Administrators perform a regular (often bi-annual) boot turn that re-images many older, off-spec machines at once so that new hardware can be deployed for higher-end use. This procedure is called cascading: the oldest hardware is repurposed with simpler software to let it continue in use for some less demanding or more access-controlled applications, but subjects it to much more rigorous control to minimize the number of images.

The total cost of operations correlates strongly to the total number of different images, not the total number of computers. To minimize the number of images requires additional discipline:

• Specify the computer hardware to minimize unneeded machine diversity and minimize the resultant number of boot images.
• Upgrade new machine specifications at low additional cost so they remain useful longer, reduce the incursion of off-spec machines later in the life-cycle, improve standardization, reduce support costs, minimize e-waste with longer lifecycles
• Organize the network so that boot images can be efficiently supported and swapped, independent of data.
  • Data must not be dependent on boot devices - use networks to store data on secure servers so that data recovery is literally never required even in a disaster recovery situation
• Confirm, by hardware acceptance testing on each new machine, that it runs the standard boot image
  • Any machine that does not must be considered to be dead on arrival
• A strict installation regime to ensure that only supportable standardized boot images are used and any machines that connect to the network for the first time with a nonstandard image are detected and rejected
• Diagnostics and troubleshooting so that help desk and other technical support staff can employ standardized tests to identify the source of problems: boot, software, or hardware
  • Ideally, backups on hand of the boot image, or even spare identical computers that can quickly be booted up from the boot device in question to determine if it is a hard disk, computer or software/image problem.
• Common desktop system recovery tools and procedures for failed desktop units, typically using backup copies of a boot image created with utilities
• Rapid network recovery procedures that replace a backup boot image in a few minutes or less, with considerable cost savings over using DVD, CD or floppy disk media which require human attention
• Ensure services for the disabled are on every departmental boot image that require them, or in the thin client hardware and software itself, to accommodate these users in a manner that is ubiquitous and cost effective.
• Support telework and secure off-site system access procedures in the standard boot image
  • Encourage teleworkers to buy identical machines to those in the office or use thin clients exclusively
• Facilitate worker transfer by changing boots or authorizations instead of moving the actual computer
• Install thin clients on all off-spec machines to eliminate the need for special boot images for them, and subsequent diagnostic problems and data risks.