Power cycling
Power cycling is the act of turning a piece of equipment, usually a computer, off and then on again. Reasons for power cycling include having an electronic device reinitialize its set of configuration parameters or recover from an unresponsive state of its mission-critical functionality, such as in a crash or hang situation. Power cycling can also be used to reset network activity inside a modem. It can also be among the first steps for troubleshooting an issue.
Overview
[edit]Power cycling can be done manually, usually using the power switch on the device, or remotely, through some type of external device connected to the power input.[1]
In the data center environment, remote control power cycling can usually be done through a power distribution unit, over the network. In the home environment, this can be done through home automation powerline communications. Most Internet service providers publish a "how-to" on their website showing their customers the correct procedure to power cycle their devices.[2][3]
Power cycling is a common diagnostic procedure usually performed first when a computer system freezes. However, frequently power cycling a computer can cause thermal stress.[4] Reset has an equal effect on the software but may be less problematic for the hardware as power is not interrupted.
Historical uses
[edit]On all Apollo missions to the moon, the landing radar was required to acquire the surface before a landing could be attempted. But on Apollo 14, the landing radar was unable to lock on. Mission control told the astronauts to cycle the power.[5] They did, the radar locked on just in time, and the landing was completed.[6]
During the Rosetta mission to comet 67P/Churyumov–Gerasimenko, the Philae lander did not return the expected telemetry on awakening after arrival at the comet. The problem was diagnosed as "somehow a glitch in the electronics", engineers cycled the power, and the lander awoke correctly.[7]
During the launch of the billion dollar[8] AEHF-6 satellite on 26 March 2020 by an Atlas V rocket from Cape Canaveral Space Force Station in Florida, a hold was called at T-46 seconds due to hydraulic system not responding as expected. The launch crew turned it off and back on, and the launch proceeded normally.[9]
In 2023 the Interstellar Boundary Explorer spacecraft stopped responding to commands after an anomaly. When gentler techniques failed, NASA resorted to rebooting the spacecraft with the remote equivalent of a power cycle.[10]
In popular culture
[edit]In The IT Crowd, Roy's go-to solution as technical support for company employees is turning their computers off and on again, often suggesting the same solution several times a day.
See also
[edit]References
[edit]- ↑ "Sun Remote System Control (RSC) Software". Oracle Help Center. Retrieved 7 August 2024.
- ↑ "Your Router May Be the Culprit for Your Slow Speeds. Here's How to Reset It Properly".
- ↑ "How to Reset Your Router the Right Way (Yes, Power Cycling Works)".
- ↑ Scott Mueller (2003). "21: Power Cycling". Upgrading and Repairing PCs. Upgrading and Repairing Series. Que Publishing. p. 1195. ISBN 978-0-7897-2745-9. Retrieved 28 January 2014.
- ↑ "Landing at Fra Mauro". NASA. "108:08:42 Haise: Antares, Houston. We'd like you to cycle the Landing Radar (circuit) breaker."
- ↑ David A. Mindell (2011). Digital Apollo: Human and Machine in Spaceflight. MIT Press. Page 247.
- ↑ Clark, Stephen (11 November 2014). "Video: Flight director updates status of comet lander". spaceflightnow.com.
- ↑ "U.S. Air Force Awards $2B AEHF Production Contract". 30 December 2012.
- ↑ "Live Broadcast: Atlas V AEHF-6". YouTube. 26 March 2020. Archived from the original on 2021-12-19. At 1:32:56, "We turned off the hydraulics and brought them back up. The parameter in question is now stable. [...] Our recommendation is to try again."
- ↑ Nancy Atkinson (11 March 2023). "NASA Fixes Malfunctioning Spacecraft The Same Way You Fix Your Troublesome Laptop". Science Alert.