How do I create a shortcut that instantly shuts down the computer in the same way the computer instantly shuts down when holding my power button for 4 seconds. This is for PC.
I tried creating a shortcut using shutdown /s /t 0 but it does not shut down instantly.
thanks.
You can't do that. That's a hardware feature (cuts power to the machine, doesn't really 'shut down').
While its not quite possible to achieve what you described as it is a hardware feature, I believe you can mimic the behavior by sending Emergency Shutdown request to system. The result would be immediate session shutdown which is comparable in time with holding the power button.
In Windows you can achieve this by using NtShutdownSystem and NtSetSystemPowerState.
There is a very nice article about this topic:
http://www.codeproject.com/Articles/34194/Performing-emergency-shutdowns
in Unix/Posix based system you should be able to do this by using:
echo 1 > /proc/sys/kernel/sysrq-trigger ;
echo o > /proc/sysrq-trigger
however you may need to obtain required privileges.
Related
I have a OpenWRT router running chrony (chronyd). The hardware doesn't have RTC, so after a power loss, the system clock goes crazy.
I want to have a LAN NTP server, but if somehow have no internet connection and the clock is wrong because a power loss, the NTP server passes the wrong time to the clients. Consider I'm using 'cheap' NTP clients (Android/Arduino/other routers/cameras) that have no way to prevent a big clock slew.
I would like to disable chrony NTP server on reboot and wait to a first sync to enable it. I thought this was a common setting, but couldn't find anywhere.
I've also tried ntpd and I'm open to alternatives (but it must run on OpenWRT).
Note: I'm already trying to use a USB GPS as a more reliable clock source even without internet connection.
My solution so far:
On chrony.conf, set to be disabled on startup.
deny all
Then, I created a script to check every minute if clock is sync (using chronyc) and then enable it again.
until ! chronyc tracking | grep "Reference ID" | grep -q "()"
do sleep 60
done
chronyc allow all
Finally, set to run script on startup.
Seems this in only possible with chrony (not ntpd), as it have a client to change settings on the fly.
I just read an article about WOL vs IPMI, it says "...used WOL to save millions of dollars by powering off idle desktops"(almost end at last paragraph but one), does it mean that WOL can be used to power off a desktop?
If so, how?
p.s. Does mainstream server support IPMI?
No, Wake On LAN lets you turn on PCs, not turn them off. The idea is that PCs need to be on in the middle of the night so they can get automatic updates; rather than leaving them on all day and all night just to get occassional updates, you can turn them off at the end of the day and use WOL to turn them on only when you need to update them.
I have written a program in Delphi 7 (includes a ModBus component that uses Indy). On my machine it uses Indy 9 and works fine. It communicates well with other machines via a ModBus protocol. However, when the program is run on a different machine, I get a CPU 90-100% load. Unfortunately this machine is not in my office but "on the other side of the world". How can I find out whether this machine is using Indy 9 or Indy 10? And, further, If it is running Indy 10, could that be the problem or is this very unlikely?
Definitive answer is No
If you compile your program with indy 9, even if using packages, it shall use INDY 9 to run. AFAIK, there's no way to compile the executable using INDY 9 and use INDY 10 at runtime, even if you want, and no way it happen by accident.
To find out whats causing the high CPU load you might try a profiler like AQTime or SamplingProfiler.
That will get you the method(s) that are running most of the time. Then you will be able to find out whats causing the problem.
Alternatively you could add some logging to your application.
To find the root cause you could prepare a test application which will go through a sequence of actions like opening / closing connections. If it asks the user for confirmation ("Continue ? y/n") before proceeding, the user can check the CPU load for every step to detect the critical operation.
Thanks for answers. I do not think this is an Indy issue though. On my Quad CPU PC the CPU load also goes up from 1-2 % to aprox. 25%. This happens if I keep the line open (connected). If I, however, disconnect the ModBus Server after every poll from the ModBus CLient side and let that PC reconnect, the CPU load is always low. WHat is normal? Having the line open all time, or connect and disconnect for every poll? The polling frequency is: in Idle mode : 2000ms, in active mode 500ms.
you need to add logs to ensure you know whats going on.
is it the connection itself that is causing you the issue? or is it the work performed while connected?
Logs will help you narrow this down and you may be able to alter you code to be less processor hungry.
using AQTime or SamplingProfiler as also suggest earlier will help you.
personally i always add logging to every application by default, alot of them require turning on but its there. Once the software it on site you never know what may change and simply turning the logs on can save you alot of time
I am writing device software for a PC and for that, I want the PC to be usable as a device. When power is supplied, it should switch on without requiring to press the power button. There are power options in BIOS settings but it starts the PC only when its uncleanly shutdown. The other concern I have is how would unclean shutdown affect the hard disk, filesystem and the OS (XP or Linux).
What you need is another PC and one of these devices attached to it.
http://www.relaypros.com/mm5/merchant.mvc?Screen=CTGY&Store_Code=NCD&Category_Code=RS-232_Relay_Boards&gclid=CMna8_yOo5wCFQxM5QodWjoflQ
What you do is send this some RS232 commands for a quick closure on one of the relays. The relay is connected to the Power On pins of the computer you want to control.
You possibly could find another relay contact closure for AC current that allows you to close a relay when AC is flowing, but you would only want to for a brief second.
Unsafe shut downs can be quite detrimental depending where the filesystem state is in. It would be quite hard on the hardware too.
There is also the alternative of booting from the network device. A quick search led to some information on wikipedia. Also, there is something related called preboot execution environment which seem to be something like what you are looking for.
Some software options - these aren't exactly what you asked for, but they might help
Mac OS X: In the energy saver control pane's options tab, select "Restart automatically after a power failue. shutdown -hu now should then bring the system down but give you 5 minutes to remove power to simulate a dirty shutdown, and have the computer reboot automatically when power is restored. It's a slightly dirty shutdown anyway, I think. (ie, it doesn't log you off first)
Windows:
I don't have a windows machine so I can't try this, but you used to be able to tell windows not to power down the computer when you select shut down, but rather to put it in a safe state and display "It is now safe to turn off your computer". Perhaps you could then remove the power and have the bios believe it was a non-clean shutdown, and turn the machine on again when power is restored. There are some instructions on how to do this in Windows Server 2003 at the bottom of this microsoft help document. This forum discussion seems to suggest it might work on XP.
Linux: Not sure about this one, but maybe this website can help.
I haven't tried any of these, so no guarantees that they'll work or work safely.
I'm using the UPS service to monitor the state of my UPS from an application -- the key at HKLM\SYSTEM\CCS\Services\UPS\Status has all the information you can get from the Power control panel. BUT -- I'd like to be able to tell the UPS to shut down from my app as well. I know that the service can tell the UPS to shut down -- for instance, after running a set number of minutes on battery -- and I'm wondering if there's some kind of command I can send to the service to initiate a shutdown manually.
I'm having trouble searching for this information -- people tend to misspell "Uninterruptible" (hrm, Firefox red-lined that but doesn't have an alternative) and "UPS" just gets hits for the shipping service. Maybe I can do something through System.ServiceController, or WMI?
CLARIFICATION: Yes, I am talking about powering down the physical UPS device. I know how to stop the service. I figured it would be a common problem -- I want my UPS to turn off with the PC. I had an idea I'm going to try, based on this page. You see, APC (and everybody else) has to supply a DLL for the UPS service to call, and since the function calls are well documented, there's no reason I shouldn't be able to P/Invoke them. I'll re-edit this once I know whether or not it worked.
Update: I tried invoking UPSInit, then UPSTurnOff, and nothing happens. I'll tinker with it some more, but the direct call to apcups.dll might be a dead end.
Check my comments to Herman, you want to shut the UPS down, not the UPS SERVICE, correct? I mean, you want that thing to shut off, kill the power, etc, right?
If so, you are looking it on a UPS by UPS model. I doubt two of them would work the same.
In your searches, instead of UPS, try "APC", or "battery". I think a lot of the code is what runs on laptops to deal with being on battery, etc...
Some place hidden in some dusty old files I have protocol information for APC UPS's, and the commands they respond to, and what they send to the PC etc. But this was WAY back in the day when we used to connect our UPS's to our computers with SERIAL cables... You could actually talk to a UPS with Qmodem or Hyperterm...
Learned it from talking to the guys at APC. They are very nice, and helpful. Now-a-days, I think you just post a URL coming from your Powerchute software, and it will talk directly to the UPS, and carry out your commands.
OK, I have the answer (tested!), but it's not pretty. My APC UPS communicates using the APC "Smart" protocol (more here). What you need in my case is a "soft shutdown", "S" command. But first you need to make sure it's in "Smart" mode ("Y"). Now, if you want to let the Windows UPS service monitor state, the service will have an iron grip on the COM port. So you can either a) let the Windows service turn the UPS off, or b) kill the service and turn the UPS off yourself.
The UPS itself has a "grace period" after it gets the "S" command, giving you time to shut down your OS. This means that to do (a) above, you have to:
Kill utility (mains) power
Wait for the Windows UPS Service timeout (default and minimum 2 minutes)
Wait for Windows to shut down -- right near the end, it will send the "S" command
Wait for the UPS grace period, after which it will actually turn itself off
I think we're going to opt for (a), just because (b) involves extra work killing the service and implementing the serial comms.
Please, tell in what language are you trying to do that... if you're using .NET you can do that with ServiceController class (read the docs).
For controlling services in Win32 API using C/C++, Service Functions (Windows).
For example to stop a service you can use ControlService function as follows (this is a quick and dirty example):
OpenService (hServMgr, TEXT("\\UPS_SERVICE_0"), SC_MANAGER_ALL_ACCESS);
SERVICE_STATUS stat;
ControlService (hUpsService, SERVICE_CONTROL_STOP, &stat)
Note that you need to provide a Service Manager handle in hServMgr and the \\UPS_SERVICE_0 name is the name that must match with your desired UPS service (either the Windows built-in or another).
Remember that to stop a service you need the proper security rights. This is not a problem with an Adminstration account, but keep in mind what happens when logging with a non-admin account.
Hope that helps.
About shutting down the physical UPS device, I remember back in WIn98 days I was able to poweroff the device talking with the UPS through the COM port, altough I don't remember the brand or how the programming interface was.