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Do Any Companies Power Down at Night?
Posted by
Soulskill
on Sun Jan 20, 2008 01:11 PM
from the when-else-can-employees-run-their-torrents dept.
from the when-else-can-employees-run-their-torrents dept.
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?"
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Submission: Does any company power down at night? by Anonymous Coward
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We power down at weekends (Score:4, Informative)
Re:We power down at weekends (Score:5, Insightful)
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.
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Re:We power down at weekends (Score:4, Informative)
Well over half a million dollars if I did the math right.
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?
Unfortunately, this doesn't always work well. On some networks, the machines will auto-start up the moment they receive a packet, even if it isn't intended for them.
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Re:We power down at weekends (Score:5, Insightful)
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.
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Re:We power down at weekends (Score:5, Interesting)
14*52*5*0.15*10000 = 5.460.000 Kwh of electric power, WORSE in the time when you use AC, because you'll need additional AC to get rid of that extra heat.
With average power-prices of 10 cent, you'll spend more than half a million dollar just paying for the electricity, in practice with AC and all you'll probably pay a million.
So, you saved $80K and wasted a million. Way to go !
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Good idea! (Score:5, Interesting)
Re:Good idea! (Score:5, Funny)
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Re:Good idea! (Score:5, Funny)
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Hibernate (Score:5, Insightful)
Really, there is no reason NOT to use the power management settings built into the OS.
Re:Hibernate (Score:5, Interesting)
It saved something like 33% power consumption (measured, before and after).
after midnight all desktops that are not in the excluded list hibernate automatically.
I used python + MFC . Was very easy and simple.
It is time for the Sysadmins start to program and make better use from the technology (not just, next-next-finish)..
And I didn't receive any raise besides saving a lot of money to University.
Shameless promotion: Looking for a new job in developed country.
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Re:Hibernate (Score:5, Informative)
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Do you support wake-on-lan? (Score:5, Interesting)
Is there some security or other downside I'm not aware of? Is WOL not reliable?
Re:Do you support wake-on-lan? (Score:5, Interesting)
Another concern is whether your servers are up to handling all the PCs coming on at once in the morning. People leaving Outlook running at all times is actually a Good Thing for IT, cause the alternative of thousands of people hitting the Exchange servers at the same minute would kneel even the biggest distributed servers. Then there's similar concerns for the domain controllers, DHCP servers, proxy servers, or you have it. Leaving a substantial part of the machine park already logged in can save a lot of hardware and configuring.
If shutting everything down, at least a staggered start-up could be prudent.
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We have power down at night policy (Score:5, Insightful)
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).
Re:We have power down at night policy (Score:5, Informative)
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Power vs. operational (Score:5, Insightful)
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.
Re:Power vs. operational (Score:5, Insightful)
Also, for the love of god, get an LCD. Modern LCDs are leaps and bounds better than CRTs in every way, especially power consumption. And they're dirt cheap too.
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I used to turn my machine off at night ... (Score:5, Insightful)
Re:I used to turn my machine off at night ... (Score:5, Informative)
Me too!
In any cases, I always leave my computer (a laptop) on during the week. I shut it off on weekends, but due to the software inventory tracker and the required anti-virus scans, I always leave the machine on during the week so that I can actually use it during the day.
The real problem is that the anti-virus scan is so slow that it takes a good three hours. The inventory scan is somewhat better, and only takes about an hour. In both cases, the machine drags to near unusable levels while the scan is running. Given that it's a dual-core machine, this is really a testament to just how screwed up Window's I/O scheduling is - both involve lots of file reads, which apparently causes Windows to drag to a crawl.
Not to mention that hibernate and to a lesser degree suspend appear to not work well with certain drivers on my system. Using hibernate kills the wireless drivers, which isn't a horribly big deal when I can physically plug the system in but it does mean that I just shut the thing off when roaming about, since I'll have to reboot anyway.
But it's that three-hour IT required virus scan that keeps me leaving the machine running nights. That's a real productivity killer during the day. Fortunately it's only scheduled to run once a week.
The inventory app, on the other hand, runs daily for some reason.
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Waste not, want not.. (Score:5, Interesting)
Then one day, they sent out a campus-wide email telling people to leave their computers on all night and over the weekend. They used the CPU cycles to run high-performance scientific computing jobs, saving the cost of buying a supercomputer.
Of course, not every company has a need for spare CPU cycles. This place did a lot of protein-shape searches etc..
workstations by day, cluster by night (Score:4, Interesting)
Re:workstations by day, cluster by night (Score:4, Insightful)
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Yes, but not strictly enforced (Score:5, Informative)
Yes and no.
When I first got comfortable in my current job, I made a big push toward "greening" our IT resources. As one obvious (erroneously, as I'll explain in a sec) step in this, I convinced most of my users to shut down at night. If we need to push out updates, WOL works just fine for turning machines on a couple hours before the start of the day, and it doesn't impact anyone during working hours.
Then I learned how electric billing actually works for commercial users - Put simply, your company doesn't care if machines stay on all night, because they pay based on their peak load, which will always occur during normal business hours. I had applied ideas that make perfect sense at home, to an environment where they don't apply.
Now, that doesn't mean we should just leave machines on 24/7 - Using electricity has an an environmental aspect in addition to the monetary cost. But if it inconveniences users by more than a few seconds every day, any conservation efforts will actually cost the company money in the long run.
So, I still encourage my users to shut down, and 95% comply. But if they consider it too much of a hassle, I can't financially justify forcing them to spend the first minute of the work day waiting for their machine to boot (not that anyone really works for the first five to ten minutes of the day, between coffee, hitting the bathroom, and just getting the obligatory morning socializing out of the way).
As for the security aspect of this, the servers must run 24/7, and any attacker would target them rather than some random user's desktop. I don't worry about an attacker using a compromised desktop as an intermediate step to the servers, because the desktops have no more privileges on them than anything else inside the firewall (and even then, not much more than a totally untrusted source, except for nonconfidential shared resources that we could restore in a matter of minutes if necessary).
Overnight tasks (Score:5, Informative)
With many enterprise management tools, such as Zenworks, it's quite simple to schedule a wake-on-lan task to wake computers up at say, 6am, to perform their daily tasks. It can even be configured to push out an automatic reimage of the machine. Once the updates and scans are done by 7am, people are just beginning to come into the office, yet you've still had a whole 10 hours of downtime. Incidentally, I've not seen a single computer in the past 4 years that doesn't support WoL on the mainboard NIC. Big bucks enterprise manglement apps aren't even required. A simple cron job, and some wakelan/ether-wake/wakeonlan/Net::Wake magic will do it for free. Just gather a list of Mac addresses with ettercap or your friendly ARP table or asset management app/spreadsheet.
May will say that the bandwidth requirements of updates squeezed into the 6am to 7am slot will degrade systems, but that's where a background process such as BITS [wikipedia.org] should be used (as demonstrated by Eve Online, Zenworks, Microsoft and Google). The virus updates are a minor bandwidth requirement if you have suitable leaf services, and the actual scan is only locally intensive.
Being a public sector organisation, we're working towards a greener profile (due to govt policies), and all the tools are there and working. It just needs some effort on the part of the administrators.
Tool to do this The Right Way from the EPA (Score:5, Informative)
Unfortunately the EPA's EZ GPO page seems to have gone poof or something recently, but you can get it here. [terranovum.com]
Basically, you push a (simple) msi to the machines (I do this a lot of the time via psexec [microsoft.com] (props to Mark Russinovich) but there are other methods. Once you have that running on the machine you can configure how you want your machines to behave/re power management:
We also have a script that runs at midnight a few days of the month that does the magic packet thing as has been mentioned so WSUS and/or SMS (or SC:CM) can do their thing and automatic updates run as normal. In a few "why does my machine have to boot up every day this sucks" user groups we have a scheduled job to send magic packets about 15 minutes before they arrive to wake up their machines. With hybernate they hardly know anything happened.
Re:Aside from being green... (Score:5, Insightful)
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Re:Aside from being green... (Score:5, Insightful)
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Re:Uh, Sleep Mode - shutdown? (Score:5, Informative)
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Re:Uh, Sleep Mode - shutdown? (Score:5, Insightful)
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Re:Uh, Sleep Mode - shutdown? (Score:5, Informative)
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viruses (Score:5, Informative)
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Re:viruses (Score:5, Funny)
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Re:Create job to force automatic reboot or shutdow (Score:5, Insightful)
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.
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Re:Create job to force automatic reboot or shutdow (Score:4, Funny)
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Re:Create job to force automatic reboot or shutdow (Score:5, Informative)
Two simple batch files for XP, on in the All Users startup directory, one in the All Users\Information Services directory of the start menu.
Startup:
AT
AT 18:00 "shutdown -t 600"
Abort:
Shutdown -a
We reset the AT table every day just in case some know-it-all high school student finds out such a thing exists and starts screwing with it. For the most part, though, not even the techs knew such a thing existed until I proposed using it.
We tried a lot of other ideas, but this is the simplest and most user-friendly. Big signs don't work, teachers and lab aids are no better than the students about following directions. Since implementing it 18 months ago, we've gone from having roughly 900 PCs online at night to about 100...including servers, timeclock systems running thinstation terminal sessions, and technology and admin workstations that are excepted from the shutdown policy.
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Re:Create job to force automatic reboot or shutdow (Score:5, Insightful)
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Re:Create job to force automatic reboot or shutdow (Score:5, Insightful)
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Re:Aside from being green... (Score:5, Funny)
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Re:Aside from being green... Just let them stay on (Score:5, Informative)
the power station does throttle down at night. they keep the generator at the same speed (3600RPM I guess, to give you 60Hz). but they don't need the same amount of fuel to keep it going. the usage on the grid acts like a brake on the generator, in the same way that the road conditions affect your bicycle.
if it's steam-based (gas, coal, nuclear), you need more steam to keep a higher pressure, to keep the generator rotating at the same speed, and that means heating more water, and more water needs more energy, and more energy needs more fuel. hydroelectric plants shut down unused turbines.
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Re:Why power down? (Score:4, Insightful)
Reducing energy consumption isn't just about saving money, it's about not fucking up the planet too.
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Re:Why power down? (Score:4, Insightful)
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Re:Why power down? (Score:4, Insightful)
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Re:Common wisdom (Score:5, Insightful)
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.)
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Re:Common wisdom (Score:4, Interesting)
I never switch any of my systems off, and failures are extremely rare. I have all monitors and flat panels automatically power down, but I leave hard drives running continuously. About the only time I have to replace something is when I upgrade every few years. Yes, it adds a few dollars to my electric bill, but I save in other areas there, and it is worth the peace of mind.
Even fans (which are the weak link in most PCs) can run for ages if you spend the money to buy quality parts. It helps to have a good HEPA filter in your computer room, and keep the machines off the floor. Fans last a long time without dust in the bearings, and a dust-free computer runs cooler as well.
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Re:Common wisdom (Score:5, Funny)
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Re:Easy fix (Score:4, Interesting)
You might be able to set up an "exception" ticket with the IT department, or set up a Magic Packet [wikipedia.org] arrangement tied to their machine.
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Re:Easy fix (Score:5, Interesting)
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Re:Easy fix (Score:4, Insightful)
Encouraging people to pull all nighters or work on weekends smacks of an inefficient workforce or ineffective management. The only times people should be working those hours are because a job sprang up last minute due to an act of god or because the work requires that it be done when people aren't around. And in those cases if you've got on sight IT, it shouldn't be that difficult to set up an arrangement to cope with that. If you're going to have work done nights and weekends anyway, you may as well just outsource things to another timezone, and that's frequently a cost saving thing anyways.
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Re:Increased probability of HDD failure (Score:5, Interesting)
There are also other benefits. A harddrive that has motors or bearings that are starting to fail can be caught when they have trouble spinning up and be replaced before they totally fail, preventing data loss. Furthermore, if a head crash occurs when no one is around (during the night or the weekend), having the the heads banging and grinding against the platters for hours or days is really going to hamper any recovery efforts.
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Re:The Green fad, is just that... marketing nonsen (Score:5, Informative)
I work for Dell. I can tell you for a fact that we take the environment seriously. The building I work in houses a 24/7 call center, but certain areas of the building are not 24/7. Corporate sales for the country are here, and take up half of the 3rd floor, for example. I happen to be in the sales department myself, and there's a piece of software installed on every desktop that hibernates the computer at 20:30 EST (with a half-hour countdown to that point). My department shuts down at 19:00, no other sales department is open past 20:00. We all open at 08:00 the next day, and the automatic hibernation sets an alarm to wake up the computer at 07:45. Alternately, if you turn your own system off through the start button and shut down, it'll stay off until you turn it back on.
We've also got computer recycling programs in place, and the "plant a tree" initiative where you can have us plant a tree for every computer you buy.
Sure. Some companies don't take going green seriously. But some do. And the number of companies that are taking it seriously is growing. Besides which, every little bit helps. Do you know the amount of energy that could be saved if everybody unplugged those electronic devices that "sleep" when they're not being used? 2W doesn't sound like much, until you multiply it by half a billion devices.
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