From PC-BSD Wiki
Revision as of 07:47, 29 December 2011 by Tigersharke (Talk | contribs)

Jump to: navigation, search
Return to Table of Contents



You will not apply my precept," he said, shaking his head. "How often have I said to you that when you have eliminated the impossible, whatever remains, however improbable, must be the truth? We know that he did not come through the door, the window, or the chimney. We also know that he could not have been concealed in the room, as there is no concealment possible. When, then, did he come?
--Sherlock Holmes in The Sign of the Four, ch. 6 (1890)

The Checklist

Just as Sherlock Holmes would investigate a crime, there is a bit of deductive reasoning involved in solving computer and software problems. Therefore, the first things to verify are usually the most obvious and may seem like a waste of time, but its essential to eliminate them before continuing. This intentionally generic checklist should help in your search for the truth and development of a solution to the problem.

Hardware Software
  1. Power/data is available from source
  2. Power cord(s) is/are attached on both ends
  3. Data cable(s) is/are attached on both ends
  4. Data cable(s) is/are connected to the proper ports
  5. Cable(s) is/are proper for situation
  6. Cable(s) is/are clean and undamaged
  7. Power switch(es) is/are in on position
  8. There is a physical indication of on and/or ready state
  9. Device(s) is/are configured to accept connections, send/receive data
  10. Device temperature/conditions is/are within its/their tolerances
  11. Plugs, ports, and/or mechanisms are clean and undamaged
  12. Necessary media matches specifications of device
  13. Necessary material(s) is/are sufficient for the task(s)
  14. Fuse or breaker has not been tripped/blown
  15. There is no unusual visible, audible, or tactile noise/effect
  16. Device(s) is/are capable of desired action
  17. Devices and models are compatible
  18. Components are properly seated and in optimal condition
  19. Device location has not changed; device has not been moved to (or from) another PC
  1. Download was complete and successful
  2. Checksum matches that provided by the download site
  3. Software/driver is installed/loaded
  4. Software/driver recognizes existence of device(s)
  5. User has authority/access to perform action(s)
  6. Internal device settings/BIOS optimal for situation
  7. File/directory has proper group and/or permission settings
  8. Firewall is set to permit service or port traffic
  9. Service/daemon/software is enabled/running
  10. Service/daemon/software is configured or initiated properly
  11. Software exists, is present, and is current
  12. Software is executed with necessary authority/access
  13. Software has not failed silently or thrown errors
  14. Dependencies are installed and proper version
  15. Configuration/data files are readable/writable
  16. Configuration file has no typo or format flaw
  17. Software/driver is capable of desired result
  18. Software works as expected in GUI, cli, or both
  19. Device enumeration matches known hardware; /etc/fstab or other configuration file is accurate

Additional Resources


Personal tools