Turn on a computer remotely

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Guest

Hello!

Are there some way to turn on a computer remotely? How could I do it? By
command line is it possible? What is necessary?

I know that we have to set an option on Bios, but what else is needed?

Thanks,
 
No. The computer is off, so it cannot recieve any remote commands.
Click to expand...

That affirmation is not correct in its generality. Most recent computers
are not just "off". Normally there is a small amount of hardware active as
long as the power supply is plugged in ("standby power"). Google for ACPI,
standby power, power management and similar terms for more information.
(Ever noticed that the on/off switch is not a normal light-switch type
switch? It's a simple push button, and its function can even be programmed
on many computers. When you switch your computer on, there's some
electronics already active that checks this switch. It's then the
electronics, not the switch itself, that powers the computer.)

Some NICs have a "wake on LAN" feature. While the computer is off, the NIC
(powered by standby power) still checks the network traffic for certain
packets and if this option is enabled in the BIOS, it can start the
computer. I have never done this, though, and don't know what kind of
application you'd need to send those packets.

Start here http://support.intel.com/support/network/sb/cs-008459.htm

Gerhard
 
It's a simple push button, and its function can even be programmed
on many computers. When you switch your computer on, there's some
electronics already active that checks this switch. It's then the
electronics, not the switch itself, that powers the computer.)
Click to expand...

I think Thorsten is correct. I checked on this and the alternatives to
using the on/off switch need to be done locally: at the machine - not
remotely as requested by the OP.

With the "wake" options, the "off" state would not work as these require
the system to be active or in some form of "sleep" to respond. On the other
hand, these could be used if the OP were to use one of the available sleep
modes on the machine in question instead of turning it off.
 
You can send a WakeOnLan message over the local network to wakeup a computer
that is off. Assuming the motherboard supports it. Most new machines do.
All you need is the network card's MAC address.

I have written software to do this, and I use this myself to power on
machines for automated backups, then power them off after the backup job has
finished.

The machines are not in standby or hibernation, they are off. Only the
network card is still on. Its also great if I am away from the machine and
I need to turn it on to access something. I use this utility every single
day for something.

http://www.aquilatech.com/Products/WakeOnLan/

Enjoy it. Freeware.
 
You can send a WakeOnLan message over the local network to wakeup a computer
that is off. Assuming the motherboard supports it. Most new machines do.
All you need is the network card's MAC address.

I have written software to do this, and I use this myself to power on
machines for automated backups, then power them off after the backup job has
finished.

The machines are not in standby or hibernation, they are off. Only the
network card is still on. Its also great if I am away from the machine and
I need to turn it on to access something. I use this utility every single
day for something.

http://www.aquilatech.com/Products/WakeOnLan/

Enjoy it. Freeware.
Click to expand...

Thanks, Croco.
 
I think Thorsten is correct. I checked on this and the alternatives to
using the on/off switch need to be done locally: at the machine - not
remotely as requested by the OP.

With the "wake" options, the "off" state would not work as these require
the system to be active or in some form of "sleep" to respond. On the other
hand, these could be used if the OP were to use one of the available sleep
modes on the machine in question instead of turning it off.
Click to expand...

The on/off switch in fact usually can't be operated remotely. But that
wasn't really the question...

You probably haven't read the Intel link I provided, and neither googled
for ACPI and "standby power" :) Pretty much all recent computers have
power supplies that provide "always on" standby power to the mobo. Just
check out ATX power supply data sheets. To make the search easier, start
here:

http://www.duxcw.com/faq/ps/ps1.htm
http://www.pcguide.com/ref/power/sup/funcSoftPower-c.html

In normal operation, even when the computer is off (not standby or
hibernation, but off), the mobo is never "dead". When off, some parts of it
are running on standby power -- among them the front panel power switch
circuit, and possibly a wake-on-LAN NIC.

Gerhard
 
Pretty much all recent computers have
power supplies that provide "always on" standby power to the mobo.
Click to expand...

I realize all of this, Gerhard. The original OP asked what their options
were if the machine was turned OFF. Of course there are options with power
management but that's not what they specified.
 
Sharon F said:
I realize all of this, Gerhard. The original OP asked what their options
were if the machine was turned OFF. Of course there are options with power
management but that's not what they specified.
Click to expand...

If the computer supports wake-on-lan, it can be turned on, even if it is
fully off. The only way it wouldn't work (assuming w-o-l is functional) is
if the computer is unplugged, or turned off at a power strip or something
similar. But most people don't do that, they just turn if off normally.
 
I realize all of this, Gerhard.
Click to expand...

By your comments, I'm not so sure whether you really realize the
ramifications of this.
The original OP asked what their options were if the machine was turned
OFF.
Click to expand...

I'm also not so sure where you got this from. Quote:
..> Are there some way to turn on a computer remotely? How could I do it?
..> By command line is it possible? What is necessary?
Click to expand...

but none of them could find the word said:
Of course there are options with power management but that's not what
they specified.
Click to expand...

There wasn't really that much "specified" other than that the OP wants to
"turn on a computer remotely". Which in a way implies that it is turned off
-- but doesn't really specify /how/ exactly it is turned off.

So what do /you/ mean when you say "the machine was turned OFF"?

Here is a possibly not exhaustive list of possibilities:

1- You put the computer into standby. I'd say that most computer-literates
wouldn't use the term "off" for this state (because you can't really unplug
the computer in this state without losing data, and because the power
supply is in a different state as when the computer is normally "off"), but
it is possible. Wake-on-LAN (WOL) works here.

2- You put the computer into hibernation. This conceivably might be called
"off" (one reason being that the power supply is in a state that's pretty
much the same as when the computer is normally "off"). A normal ATX power
supply provides the mobo with standby power in this state, and WOL works
here.

3- You use the Windows "shutdown" command or something similar (that is,
you use another way to invoke the same function). This is probably the most
"normal" case of "off". A standard ATX power supply provides the mobo with
standby power in this state, and WOL works here.

4- You press the power button for more than 4 seconds. After this, the
computer is in the same state as after #3 above. That is, standby power is
available, and WOL works.

5- You switch off the power switch at the power supply at the back of your
computer (if your power supply has such a switch). If it exists, this is
usually a "hard" power switch, and in this case no standby power would be
provided, and WOL wouldn't work.

6- You cut the power supply to the computer (unplugging it, switching off
the power strip, etc.) Same as with #5: no standby power, no WOL.


Now I'd say that what most people would call a "switched off" computer is
something like 3, 4 and maybe 2. In all these cases, WOL can work (because
the mobo gets standby power and can supply the NIC with it). It can't work
in cases 5 or 6, but I'm reasonably sure that the OP would imagine this.

Gerhard
 
3- You use the Windows "shutdown" command or something similar (that is,
you use another way to invoke the same function). This is probably the most
"normal" case of "off". A standard ATX power supply provides the mobo with
standby power in this state, and WOL works here.

4- You press the power button for more than 4 seconds. After this, the
computer is in the same state as after #3 above. That is, standby power is
available, and WOL works.
Click to expand...

Thanks, Gerhard, for your patience. Don't know why I kept fixating on "off"
and appreciate your explanations about the finer points of modern power
management.
 
If the computer supports wake-on-lan, it can be turned on, even if it is
fully off. The only way it wouldn't work (assuming w-o-l is functional) is
if the computer is unplugged, or turned off at a power strip or something
similar. But most people don't do that, they just turn if off normally.
Click to expand...

Thanks, D. Currie. Have answered questions about this before but for some
reason had a blind spot this go-round. Go figure. :)
 
I wonder if you can use and configure an internal modem with "wake on ring"
and then connect your modem to the phone line and when you wish to turn the
machine on just give the number a call from any location on the
planet..........
 
Yes, if the BIOS supports this (most do) and you have configured it
correctly. One problem is that wrong numbers, people selling double
glazing, and the like, will also turn the computer on!

In the dim and distant past (the days of DOS 4.0 and Windows 3.1!),
you could buy power strips that could be hooked up to a phone jack and
would power up the connected device(s) (either for a preset period or
until they were turned off again) when the "phone" rang. I used one of
these to allow me to dial in to a computer at my office. This was
configured to boot up into an ancient terminal server program (ProComm
Plus, in server mode) which allowed me to transfer files. The
computer's modem and the remote power switch were connected in
parallel - You had to dial the number from a regular phone, let it
ring a couple of times, and then hang up. After waiting an appropriate
time for the remote computer to boot up, you called back from your
modem and connected to the server software.

I wonder if you can use and configure an internal modem with "wake on ring"
and then connect your modem to the phone line and when you wish to turn the
machine on just give the number a call from any location on the
planet..........


Sharon F said:
Thanks, Gerhard, for your patience. Don't know why I kept fixating on
"off"
and appreciate your explanations about the finer points of modern power
management.
Click to expand...


Please respond to the Newsgroup, so that others may benefit from the exchange.
Peter R. Fletcher
Click to expand...
 
I wonder if you can use and configure an internal modem with "wake on
ring" and then connect your modem to the phone line and when you wish to
turn the machine on just give the number a call from any location on the
planet..........
Click to expand...

Look into your BIOS. It might have that option. I have a desktop that can
do that with modems with a "real" COM interface; i.e. almost for sure no
winmodems, and possibly no internal modems of any kind. And I have a
notebook that can do that with the (internal) winmodems it was designed to
work with.

The BIOS needs to be able to understand the ring signal from the modem. It
is defined in a reasonably generic way for COM port based modems (whether
external or internal), so they can put a generic COM port driver into the
BIOS that understands the generic ring signal. It also is reasonably
defined for computers (usually notebooks) that can assume a specific
selection of winmodems, so they can put a minimal driver for just those
types into the BIOS.

There might be problems with the internal modem's power supply, though,
unless both the BIOS and the modem are actually designed for that (like
with my notebook). I've only ever done this with external modems, which
then of course are powered independently.

I guess it's RTFM time, and you need to have a look at your mobo's manual
:)

Gerhard
 
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