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Do Any Companies Power Down at Night?
An anonymous reader writes "My Health Sciences Campus has about 8,000 desktop computers, and on any given night about half of them are left on. I know this because I track all the MAC addresses in case there is a virus outbreak. Aside from the current fad of 'being green', has anyone had any success in encouraging users to power-down at night? You could potentially eliminate running bots, protect yourself from the next virus outbreak, keep your data safe, etc. Do security concerns and power consumption issues matter enough to do this?"
It's time that all large campuses configured their systems hibernate automatically, if left unused for 30 minutes.
Really, there is no reason NOT to use the power management settings built into the OS.
The answer is simple. Tiny minority of the computers that are on could still be used by someone doing something important. You do not want to cut them off from the network.
I work for a large blue chip company and we have a strict policy of powering down at night (including monitor). We regularly audit the records to ensure the machine is powered down and users who are not are requested to always remember. A few users take a few reminders in order to do so and I have heard every excuse under for why they left it on and while some are valid the majority (95%) are not. Our reasons for pushing this policy is purely to save money and reduce unnecessary running time of the equipment. However we are in a position where only laptops users have VPN access so if they need to login to the network from home they already have their laptop with them. If we had open VPN access to desktop users I am sure we would see a lot of users leaving their computer on so that they can RDP into it over VPN.
It took about 6 months before we were at a realistic level. We have 633 desktops on our site so there is normally always a valid reason for one or two to be left on (valid reasons being batch copy, verify or processing of files). For those interested we have had a reduction in the amount of equipment failure (HDD mainly) as well as pretty good cost savings for power. Not to mention running greener (which regardless of if you believe in global warming or not is good).
I tend to leave the computer on overnight, but with things like monitor power-down and CPU idling enabled. When it's not doing anything it drops about 90% of it's power consumption after 15 minutes, and even when working with the monitor off (eg. running the nightly backup) it's still running at less than 50% of full power. If I power it off, by comparison, it can't run it's virus scan, backup, update check and the like overnight and has to do those things while I'm trying to use it during the day. Plus there's wear and tear to consider, I've noticed that the office computers that get turned off and on every day tend to fail and need replacing several times before mine (that stays on all the time) has a failure.
So my preference is to leave computers running but with power-saving features set to minimize power without shutting things down. This means hard drives continue to spin but the CPU goes into low-power idle mode. The monitor goes to suspend mode (beam and deflection power is off but the circuits and coils are kept warm), not powered-down completely. That seems to be the best balance between reducing power consumption, allowing it to run maintenance operations overnight and minimizing wear and tear and thermal stress on the components. If management absolutely insists on ignoring those last two in favor of the first, wake-on-LAN is essential to allow nightly maintenance to happen.
... but now IT has loaded so much crap on it ("desktop agents" [ie apps that spy on me], antivirus, patches, etc) that it is fully 15-20 minutes after turning it on before it is usable. So now I never turn it off. I did the hibernation thing for awhile, but then it stopped working for some reason and I haven't been able to fix it. And if I ask IT to fix it, their solution is always the same for every problem - wipe the machine - a tad inconvenient for me, but pretty efficient for them I suppose. Sigh.
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Reducing energy consumption isn't just about saving money, it's about not fucking up the planet too.
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1: Power-cycling actually reduces the MTBF opposed to just leaving it on.
2: The reduced MTBF is lower than your company intends to keep the asset.
3: Cost-savings from the "increased" MTBF by leaving it on is greater than the electricity (+ increased A/C cost) cost to run those 300W power supplies all the time.
Of the ~6 computers I've had to failure, they all lasted far longer than even a five-year technology plan, AND did not fail due to simple wear and tear on the circuits. My anecdote isn't data, but it does make me question your conventional wisdom. (Especially since those PCs I know that are left on all the time don't have a significantly increased lifespan.)
What's the cost of 10k * 261 days * 12 hours of power?
Surely you could use wake on lan to wake the machines then do your rollout 10 minutes later? Or do a patch install when the machine is turned on and connects to the domain controller?
In windows I'm sure you can set the time between warning appearing and shutdown ocuring. Give 600 seconds warning and you could probably shutdown 90% of the machines overnight.
Someone might be using it ... there are always a few late users. Trying to determine if a computer is in use in order to shut it down isn't always that simple.
... it won't be a 100% solution, but most people would probably comply, so for the comparatively little effort put in I bet you can hardly get a better return.
I suggest a simpler, low-tech solution - just stick up visible signs in the labs, and on some of the major office floors, asking people to shut down the computers in the evenings
Just the energy savings on that many computers would be not insignificant.
In windows I'm sure you can set the time between warning appearing and shutdown ocuring. Give 600 seconds warning and you could probably shutdown 90% of the machines overnight.
You're assuming that 100% of machines in use are doing something interactive (and therefore have someone sat at them). This is frequently not the case.
Well, in a university, "scientific calculations" could mean actually running simulations/models/whatever, that is, things for which you would normally use some super computer. So it is not necessarily a question of "getting away with this", it might make perfect operational sense and boost the uni's available computational power and thus productivity. Depending on what industry you work in, you could do a similar thing in a company, for example a nightly distributed build-and-extensive-regression-test in a software shop, and save on purchasing and operating dedicated computers. There are lots of quite productive uses for distributed computing. You just need to think about what your company might do with it. Of course, if there is no productive thing the computers could be doing, they are better turned off.
Amen to that. I doubt anyone really wants to pull an all-nighter, they're there because there's a deadline coming or a problem that must be resolved right now. And whether true or false, the first time anyone uses the excuse "Well, I was ready to pull an all-nighter but from 10pm the network was down" the IT department will have their ass chewed out. PCs inactive -> PCs hibernate is ok, but even then you need a simple way to disable it. On several occasions I've visited copmanies that had boxes which were "don't touch - accessed remotely by VPN" where the user couldn't just unhibernate it in the morning. Plus funny stuff like updates, virus scans and backup (if applicable) that probably runs at some ungodly hour which means you need to wake them first or lose most of the downtime, run those and put them back into sleep. Sure, maybe you could get every PC do to this reliably but I think the administration and scripting of that will cost you quite a bit.
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Why not just have the machine shut down automatically on logout if it's between two specified times (eg. 9pm and 8am)?
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The student who walked away from (or, fell asleep at) the PC without saving learns a valuable lesson.
In a corporate environment, that sort of decision is made at a corporate policy level, and not at an IT personnel level. Nobody would get fired.
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