Tag: WOL

Wake On Lan (WOL)

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WOL – Think of it as getting your computer to rise and shine like a reluctant teenager on a school day, with a little extra help from your digital toolkit so those remote/scheduled jobs can run.

So, Here are some notes put together that helped/got me going:

1) Check hardware compatibility & prerequisites:

  • Your computer’s motherboard and network adapter (NIC) support WOL.
  • You’re using a wired Ethernet connection (Wi-Fi is unreliable for WOL).
  • Your switches and routers allow broadcast packets (some block them by default).
  • Your network adapter drivers are up to date.

2) Enable WOL in BIOS/UEFI (Dell Optiplex 7060 example):

  1. Restart your computer and press "F2” to enter the BIOS setup.
  2. Navigate to Power Management Settings.
  3. Locate the Wake-on-LAN option (sometimes called “Power On by PCI-E” or “Remote Wake-Up”).
  4. Enable the setting.
  5. Ensure the Deep Sleep is off, otherwise Wake-on-LAN won’t work.
  6. The “last state” on Power Recovery – may want to set to “Power On” as its totally unreliable if set to default (power off).
  7. Save changes (F10 to exit and save).

3) Configure network adapter in Windows:

  1. Open Device Manager (Win + X → Device Manager).
  2. Expand Network Adapters and find your Ethernet adapter.
  3. Right-click and select Properties.
  4. Go to the Power Management tab:
    • Check “Allow this device to wake the computer”.
    • Check “Only allow a magic packet to wake the computer”.
  5. Switch to the Advanced tab:
    • Enable Wake on Magic Packet.
    • Enable Wake on Pattern Match (optional).
  6. Click OK to save settings.

4) Check and configure your VLAN for Directed Broadcasts:

For WOL to work across VLANs, the switch must allow the magic packet’s directed broadcast. Here’s how to check and configure it on a Cisco switch (similar concepts apply to HP/Aruba switches):

Log in to Your Switch:

Use SSH or console access.
Enter privileged EXEC mode:

Switch> enable

Locate and Verify the VLAN Interface:

List your VLANs:

Switch# show vlan brief

Identify the VLAN where your WOL-enabled device resides (e.g., VLAN 10).

Enter Global Configuration Mode and configure the SVI (Switch Virtual Interface) for “Directed Broadcast“:

Start configuration:

Switch# configure terminal

Enter the interface configuration for your VLAN’s SVI:

Switch(config)# interface vlan 10

Assign an IP address (if not already set):

Switch(config-if)# ip address 192.168.10.1 255.255.255.0

Enable Directed Broadcasts on the VLAN interface:

Switch(config-if)# ip directed-broadcast
  • (Note: Some switches may require enabling this via the GUI)

Exit configuration and save changes:

Exit the interface configuration:

Switch(config-if)# exit
Switch# write memory

Verify Your Configuration:

Run:

Switch# show running-config interface vlan 10
  • Look for the ip directed-broadcast line. If it’s present, the VLAN is now set to forward directed broadcast packets.

For non-Cisco switches (HP/Aruba):

  • HP/Aruba: Look for “Forward Net Directed Broadcast” in the web GUI or CLI under VLAN settings.

Adjust firewall and router settings:

  • Open UDP Port 9 (or 7):
    Ensure your firewall allows UDP traffic on port 9 (or 7), which is used for WOL magic packets.
  • Allow Directed Broadcasts Across Subnets:
    If your router sits between different network segments, configure it to allow directed broadcasts.

Configure SCCM for WOL (optional):

If using System Center Configuration Manager (SCCM):

  1. Open SCCM Console.
  2. Navigate to Administration → Site Configuration → Sites.
  3. Right-click your site and select Properties.
  4. Under Wake on LAN, enable “Use Wake on LAN”.
  5. Configure UDP ports (default is UDP 9, but some setups might use UDP 7).
  6. Deploy a scheduled task that sends WOL packets before maintenance windows.

Send a WOL command:

Now for the fun part—waking up your machine remotely! You can use PowerShell or a third-party tool like Wolow.

PowerShell Example

Send-WakeOnLan -MacAddress "00-11-22-33-44-55" -IPAddress "192.168.1.255" -SubnetMask "255.255.255.0"

This sends a magic packet to wake up the machine.

Using Wolow App

  1. Install Wolow on your phone.
  2. Add your PC manually or scan the network.
  3. Tap the power button to wake up your computer.

Automate wake, task execution, and sleep:

Want your machine to wake up, run a scheduled task (like Delprof to clean profiles), and then go back to sleep? Try this:

Wake up & run task

Start-Process -FilePath "C:\Scripts\Delprof.exe" -ArgumentList "/q /i"

Put the computer back to sleep

rundll32.exe powrprof.dll,SetSuspendState Sleep

Final thoughts…

Setting up WOL is like training your computer to respond to a digital alarm clock. Once configured, it’s a game-changer for remote management, scheduled tasks, and energy efficiency.

If you run into issues, check:

  • BIOS settings (some updates reset WOL).
  • Network adapter settings (ensure magic packets are enabled).
  • Firewall rules (UDP ports must be open).
  • VLAN settings (directed broadcasts must be enabled) – this is the one that is easy to get caught on.

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Photo: Alan W.