Wake-on-LAN

This small command line utility makes possible to switch on a computer from a second one by sending a “Magic Packet”. Both of computers can be located on the same LAN or on the different LAN segments.

Requirements to use the WOL (Wake-On-LAN)

  • An ATX motherboard with an onboard, 3-pin “WOL” connector.
  • An ATX power supply that meets ATX 2.01 specifications.
  • A network card that can support WOL with its cable to the motherboard properly installed.
  • In the BIOS Power Management, you must enable the LAN Wakeup option.
  • How to use MC-WOL
    Use the following command in a Windows DOS box:  MC-WOL ethernet-address [/a ip-address] [/p password]
    A description for each argument follows:

  • ethernet-address – Ethernet MAC address of the network adapter of the destination computer.
  • ip-address – Multicast IP address of the LAN (see below) where the destination computer is located. This argument is not required if computers are located on the same LAN.
  • password – Is only required for a few adapter types. The password should be specified in ethernet hex format (i.e. 01:AA:02:BB or 01:AA:02:BB:03:CC:04:DD).
  • Example1: MC-WOL 00:01:02:58:A3:C7
    If a target computer is on another LAN, IP address must be specified. For example you have a segment using the class C network 192.168.5.0. The broadcast ip address of this subnet is 192.168.5.255 – that’s what you use as the destination IP address on the packet.
    Example2: MC-WOL 00:01:02:5C:A1:B2 /a 192.168.5.255
    This multicast packet will be delivered by router(s) to the ethernet switch that comprises the network segment.

    How to get MAC address
    You can use our freeware utility MCGETMAC.EXE, to obtain ethernet address of the NIC (network interface card) of the target computer.
    Usage: MCGETMAC ip-address or name

    Download MCGETMAC.EXE
    Download MC-WOL.EXE

    See also:
    Remote Shutdown

    http://www.matcode.com/wol.htm

    Note: Wake On Lan is a trademark of IBM Corporation.

    What is WOL?

    Quite simply, WOL is a technology that allows a computer that is turned off to be remotely turned on.  While there are a number of different protocols for implementing WOL, Hyena currently only supports the ‘Magic Packet’ tm technique.

    How does it work?

    WOL-enabled computers must have a network adapter installed in them that supports one or more remote wake up protocols.  The general technique used by WOL-enabled network cards is that even when powered off, the computer’s network card still receives a small amount of power to enable the card to ‘listen’ for a special signal on the network to wake up.  At that point, it instructs the computer to turn itself on.  Hyena supports the most common WOL protocol, the ‘Magic Packet’, whereby a specially formatted network packet is sent to the computer address to wake up.

    To learn more about WOL, visit http://www.depicus.com/wake-on-lan

    The key to implement WOL is to know the remote computer’s (the one to be awakened) MAC address.  The MAC address is used since the computer is OFF, and any tcp, registry, etc. services are not available.  There are a lot of ways to get the MAC address – some sample ways are:

      • Issue the command “ipconfig/all” on the command line to get all installed card addresses.
      • Use the WinMSD utility to view the network card address information.
      • In Hyena, select Computer Properties, select the Network dialog, and look at the Transports section, or use a WMI query to retrieve the address.  Exporter Pro can also be used to export either transport or WMI card address information.

    Hyena WOL Settings

    To configure the WOL settings in Hyena, go to Tools->Settings->WOL.  In order to have a consistent technique to always having the MAC address for any computer, Hyena relies upon a simple text file of the addresses for any computer that WOL support will be needed for.   This file also can contain custom network broadcast address and/or port assignments that can further tailor the WOL functionality for different environments.  The settings for the WOL options all relate to this file, which is called the “WOL Configuration File” in this documentation.

    WOL Network Configuration File Location – By default, Hyena will look for a file named “wol.dat” in the same directory as Hyena’s other configuration files.  By default, this location is either the user’s profile directory, for example C:\documents and settings\<username>\application data\systemtools\hyena, or (if specified) the shared settings location under “General” settings.   To use the default locations, leave this setting blank (empty).  If, however, it is desired to have a different location for this file enter the path and, optionally, the full name of the WOL Configuration File.   Use the Edit button to quickly view or edit this file.  See the WOL Configuration File Format section below for the content specifications.

    Default Broadcast Address – By default, the broadcast address used to send all WOL requests is 255.255.255.255, unless a specific address has been specified in the WOL Configuration File.

    Default Port – Enter a port to send all WOL requests to by default.  The Default Port will be used only if a specific port has not been specified in the WOL Configuration File.

    WOL Configuration File Format

    The format of the order of fields in the WOL Configuration File is:

    Host Path – This is the path to the remote computer and is used by Hyena to match the computer(s) selected in Hyena to the entries in the WOL Configuration file.  Generally, this path can be entered as the Netbios computer name, unless the computer is in an Active Directory domain and the “Use DNS Computer Paths” option is enabled under Tools->Settings->Active Directory.  If the computer is part of a manual Object Manager entry, use whichever format of the path was entered in Object Manager.

    MAC Address – Enter the MAC address in the standard “00:AB:34:FA:54:CD” format.  Either colons or dashes may be used to separate each hex pair.

    Broadcast Address – If desired, enter the ip address to direct the WOL request to.  For many environments, this address can be a broadcast address of 255.255.255.255.  Optionally, it can be left blank and entered manually when the actual WOL request is sent.  A single dash ( – ) can also be entered into this field to make the WOL Configuration File easier to visually manage.

    Port Address – Enter the port to send the WOL request through.  If left blank a default port will be used.  A single dash ( – ) can also be entered into this field to make the WOL Configuration File easier to visually manage.

    IMPORTANT NOTE: All fields must be TAB delimited.

    A sample line from a typical WOL data file would appear as follows (using default port and broadcast address):

    hostname 00-07-E9-07-8C-B1

    Other information can be entered into other fields in this file as long as the first four (4) field elements are as previously described and separated by tabs.  A tab must also follow the port address if other fields are added after the port address.

    Initiating a WOL request to a remote computer

    To send a WOL request, select one or more computers, and select the Send Wakeup Request… from the computer context menu.  A dialog will be displayed that supports setting a specific broadcast address or port number for any selected computers IF the broadcast address and/or port number have not been assigned to the computer(s) in the WOL Configuration File.  The WOL Configuration file can also be viewed/edited from this dialog.

    Clicking OK will send the WOL request to all selected computers.  An error will be displayed if a matching entry in the WOL Configuration file cannot be found or if an error is returned by the network.   Note that there will not be any success/failure indication if the remote computer received and processed a WOL request, as the WOL protocol does not support this.

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