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Shutting down
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Network Sorcerer enables you to shutdown, suspend, hibernate,
lock and Wake-on-LAN (WOL) other computers on your network.
Just select the required command from the taskbar menu.
1. Left: Selecting an action from the menu.
NOTE:
To shutdown, suspend, hibernate, lock or wake a
group of computers, you can create a Global Task List.
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2. Below: The action is confirmed by the target machine.
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In order to perform most of these tasks (wake-on-LAN excluded), Network Sorcerer
must also be installed on the target computer.
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Waking Up.
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3. Right: Send a Wake-on-LAN magic packet.
There's no need to know the target machine's MAC address.
To wake a group of computers you can create a Global Task List.
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4. Below: The target machine is back on-line.
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Windows power states and Wake-on-LAN (WOL).
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Initially, there are two basic modes to consider in relation to MS Windows and Wake-on-LAN
magic packets:
- The computer is fully disconnected from the wall socket - switched off or unplugged,
(if you press the machine's 'on' button it will NOT start-up).
Wake-on-LAN can never start a computer from this state.
Even if the supply voltage is subsequently connected, most computers will still
not respond to a wake-on-LAN magic packet. see: Mechanical Off
- The computer is off but connected to the supply,
(if you press the machine's 'on' button it will start).
If the computer has not been booted since it's supply was last connected, then it
will probably not respond to a wake-on-LAN magic packet. see: Mechanical
Off
If the computer HAS been booted and later shutdown,
hibernated, suspended, set to standby or sleep, it
can most likely be woken by a wake-on-LAN magic packet. see: Soft
Off
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Shutdown
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Known as 'Soft Off' or S5, this is the completely off state arrived at by
shutting down a machine from its 'on' state. It is NOT the same state as
that arrived at by tuning a machine 'on' from a fully 'mechanical off'
state (known as G3). When a correctly configured computer is in a 'Shutdown'
(S5 'Soft Off') state it can usually be woken by a wake-on-LAN magic packet.
Most hardware, when freshly connected to the power supply from a fully 'mechanical
off' (G3) state, can NOT be woken by a wake-on-LAN magic packet.
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Hibernate
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Saves an image of your computer's memory to the hard drive thus allowing the
machine's state to be completely preserved - even when it is disconnected from
its power supply. A correctly configured machine that has been sent into hibernation
can be resumed by a wake-on-LAN magic packet. Wake-on-LAN will most likely NOT wake
the device if its power supply was interrupted (G3 state) between reaching hibernation
and receiving the wake-on-LAN magic packet.
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Standby, Sleep or Suspend.
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It is difficult to determine true 'separate' meanings for any of the above states
or indeed, what order or relationship may exist between them. Different BIOS and
OS settings will produce varied results and also, due to ambiguous descriptions,
historical inconstancies and misconceptions over the years, many people and indeed
many authorities, harbour conflicting opinions as to what should do what. For example,
the ACPI specification defines seven states, three of which are all described as
a Sleep' state and one of these (S3) has been simultaneously described as 'Standby',
'Sleep' and 'Suspend' (to RAM). The current fashion seems to favour 'Sleep' as a
general name for this 'lite off' mode and this fits well with the deeper 'Hibernate'
state. Whatever they're called, these are low power, energy saving states that are
not quite as deep or efficient as hibernate or shutdown - and lurk somewhere within
the ACPI modes S1 and S3 - where the computer attempts to cut power to all unneeded
parts of the machine apart from the RAM which is required to restore the machine's
state. Waking from one of these states varies depending upon it's depth and the
machine's configuration. The lightest being most quickly and easily woken - typically
by pressing a key on the keyboard or moving the mouse, deeper versions will only
wake with a press of the 'on' button. On a correctly configured machine, all versions
can be woken by a wake-on-LAN magic packet.
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Wake on LAN, the full picture.
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What is Wake-on-LAN
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Wake-on-LAN provides the ability to turn-on a remote computer across a network (or even across the internet)
by sending a special signal called a magic packet. Magic packets can only be handled
by network cards and motherboards that are Wake-on-LAN compliant.
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How does it work?
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Wake-on-LAN operates in the following manner: after a computer has shut down, the
network interface still receives power and keeps listening on the network for a
magic packet to arrive. If a magic packet is received, a boot sequence is initiated.
The wake-on-LAN magic packet is different for each computer and basically consists
the machine's MAC address (a unique identifier associated with its network interface)
repeated a fixed number of times. Because of the way operating systems now integrate
with the modern BIOS, a Wake-on-LAN magic packet may also wake a computer from sleep
or hibernation.
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Configuring Wake-on-LAN Hardware
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If the computer has a separate PCI LAN card, you will have to enable Wake-on-LAN
functionality for PCI devices in your BIOS. If it has a motherboard with a PCI 2.1
bus (or older), you'll need a 3-pin Wake-on-LAN cable connected between the
card and the motherboard. This cable is not generally needed for newer computers
using a PCI 2.2 bus (or later). Finally, check the Advanced Properties tab of the
network card. In Windows, on the card's properties Advanced tab check that Wake
functionality is enabled. Look for something like 'Wake Up Capabilities'
and set it for Wake-on-LAN. Many motherboards today have built in network cards
that support Wake-on-LAN. You will need to enter the 'Power Options' page
of the computer's BIOS settings to enable it. The process is different with
each motherboard. The setting will be called something like 'Power On By PCI
Devices' or 'Resume by MAC LAN'. Finally, you must assume that for all
intents and purposes, wireless items can't be woken with 'Wake-on-LAN'.
Most wireless stuff will power-down its wireless network interface when made to
shutdown and will therefore NOT be capable of detecting any Wake-on-LAN magic packets
once power has been lost.
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Wake-on-LAN and Windows.
What to expect...
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Mechanical Off
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The very first power state encountered when connecting a computer to its wall socket
is known as G3. This is also known as 'Mechanical Off' and can be defined
as the state where the PC receives no power or when power is first applied to the
PC but prior to the first boot (before the 'on' button is pressed) and is
the same state as that attained by holding in the power button until the machine
shuts down. In this sense, G3 is the most problematic state for those who yearn
for a Wake-on-LAN utopia because, for all intents and purposes, one must assume
that a computer can NOT be woken from this state by a Magic Packet. Often, the G3
state -with power available - is a limbo state where no wake events are possible
and ACPI devices, including network adapters are shut down. Thus it must be discounted
as a Wake-on-LAN candidate, forcing you to defer to the 'control freak'
OS ACPI for Wake-on-LAN control. Which in turn means that for every computer that
has been returned to power after an outage, someone has to physically press the
machine's 'on' button and then, once that machine has booted, shut it
back down into one of the soft power modes so that Wake-on-LAN once again becomes
available. Ways around this include running the machine on an uninterruptible power
supply or telling the BIOS to always return the machine to the 'on' state
after a power outage.
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Soft Off
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The sister state to 'Mechanical Off' is 'Soft Off' (S5). This is
the state arrived at once the machine has booted to Windows and has then been shut
down again. Once 'Soft Off' has been reached, the ACPI parts of the computer's
hardware will have become 'managed' and if the network controller's
Power Management tab has 'allow this device to wake the computer' checked,
then Wake-on-LAN will now be available until the machine is disconnected from the
power once more. Having said this, some Windows systems don't even allow Wake-on-LAN
from the 'Soft Off' state. Windows Server 2003 for instance, doesn't
support waking from the (S5) state, only from standby (S3) or hibernate (S4). When
shutting down the system, it shuts down ACPI devices, including network adapters.
This disarms the adapter's remote wake up capability. However, most motherboards
allow you to override the operating system and wake from an S5 state anyway. If
there is no support for wake from S5 state in your BIOS settings, you are limited
to Wake From Standby when using these operating systems in ACPI computers.
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Conclusion
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If purchasing from new and Wake-on-LAN is of paramount importance, make sure that
you obtain a machine capable of handling Wake-on-LAN from first switch-on. Otherwise,
examine the wake options in your machine's bios. Be prepared for only using
Wake-on-LAN to wake your computer from one of the soft power states.
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