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Wol

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What it does

The wol tool sends Wake-on-LAN (WoL) magic packets to power on devices remotely. Every network-connected device with WoL support has a network interface that can listen for a special UDP packet while powered down (if properly configured in BIOS/firmware). When netglance detects this packet, the device wakes up.

You can send packets to: - A specific MAC address directly - A named device from your netglance inventory - Any broadcast address (for subnet-directed broadcasts across VLANs) - Custom UDP ports (default is 9)

This is useful for scheduled device wake-ups, testing network resilience, and managing devices across your home lab.

Quick start

Send a magic packet to a device by MAC address:

netglance wol send 00:11:22:33:44:55

Wake a device by its inventory name (must exist in discovered devices):

netglance wol wake my-laptop

Send a packet to a specific broadcast address and port:

netglance wol send 00:11:22:33:44:55 --broadcast 192.168.1.255 --port 7

Output as JSON for scripting:

netglance wol send 00:11:22:33:44:55 --json

Commands

netglance wol send

Send a magic packet directly to a MAC address.

netglance wol send <MAC> [options]

Arguments: - MAC — Target device MAC address. Supports formats: AA:BB:CC:DD:EE:FF, AA-BB-CC-DD-EE-FF, or AABBCCDDEEFF.

Options: - --broadcast, -b <ADDRESS> — Broadcast address to send the packet to (default: 255.255.255.255). Set this to your subnet's broadcast address (e.g., 192.168.1.255) for subnet-directed broadcasts. - --port, -p <PORT> — UDP destination port (default: 9). Some devices listen on port 7 instead; try this if the default doesn't work. - --json — Output result as JSON instead of a formatted panel.

Example: 

netglance wol send 00:11:22:33:44:55 -b 192.168.1.255 -p 9

netglance wol wake

Wake a device by its hostname from the netglance inventory.

netglance wol wake <DEVICE_NAME> [options]

Arguments: - DEVICE_NAME — Device hostname as discovered and stored by netglance. If you haven't run netglance discover yet, you'll need to do so to populate the inventory.

Options: - --broadcast, -b <ADDRESS> — Broadcast address (default: 255.255.255.255). - --port, -p <PORT> — UDP port (default: 9). - --json — Output as JSON.

Example: 

netglance wol wake my-laptop --broadcast 192.168.1.255

Understanding the output

Magic packet structure

A WoL magic packet is a 102-byte UDP datagram containing: - 6 bytes of 0xFF (the "preamble") - 16 repetitions of the target device's 6-byte MAC address

The NIC recognizes this pattern even when the host is powered down, triggering a wake signal to the motherboard.

Result fields

When you send a packet, netglance returns:

  • Status — Sent (green) if the UDP datagram was successfully transmitted to the network. Failed (red) if a socket error occurred.
  • MAC — The target MAC address.
  • Broadcast — The broadcast address the packet was sent to.
  • Port — The UDP port used.
  • Device — The friendly device name (only shown when using netglance wol wake).

Important: A "Sent" status means netglance successfully sent the packet to the network. It does not guarantee the target device will wake up—that depends on BIOS/firmware configuration, network topology, and firewall rules.

  • Discover — Populate your device inventory with MAC addresses and hostnames. You must run this before using netglance wol wake.
  • Identify — Assign friendly names to devices in your inventory for easier reference.
  • Uptime — Monitor when devices come online. Pair with WoL to wake a device and then verify it's responding to pings.

Troubleshooting

Device doesn't wake up after sending the packet

  1. WoL must be enabled in firmware
  2. Restart the device and enter BIOS/UEFI setup (usually F2, F10, Del, or Esc during boot)
  3. Look for "Wake on LAN," "Magic Packet," or "WoL" options

  4. Ensure the NIC is powered when the system is off (sometimes labeled "Power from PCI-E" or similar)

  5. Device NIC must support WoL

  6. Older network cards may not support WoL
  7. Verify your NIC driver is installed and up-to-date

  8. On Linux/Mac, check driver with: ethtool <interface> (Linux) or system settings

  9. MAC address is incorrect

  10. Run netglance discover to scan your network and confirm the device's actual MAC
  11. Verify using ip link show (Linux), ipconfig /all (Windows), or ifconfig (Mac)

Packet sent but across a routed network

WoL magic packets use broadcast addresses, which don't cross router boundaries by default:

  • Same subnet: Use the subnet broadcast address (e.g., 192.168.1.255 for a /24 network). Find your broadcast with ipcalc or network scanning tools.
  • Different subnet/VLAN: Many enterprise routers support subnet-directed broadcasts or directed broadcasts. Try sending the packet to the target subnet's broadcast address using the --broadcast flag.
  • Across the internet: Standard WoL cannot reach across the public internet. Some routers support WoL over WAN features; consult your router's documentation.

Port 9 doesn't work, try port 7

The default WoL port is 9, but some devices listen on port 7 instead (the discard port):

netglance wol send 00:11:22:33:44:55 --port 7

If neither works, check your device's WoL documentation or driver settings.

Firewall blocks the packet

If your local firewall (iptables, nftables, pf) is running, ensure it allows inbound UDP on port 9 (or your custom port) from the broadcast address:

# Example: Allow WoL on macOS (pf)
sudo pfctl -e  # Enable pf if not already on
echo "pass in quick on en0 proto udp from any to 255.255.255.255 port 9" | sudo pfctl -f -

No devices in inventory for netglance wol wake

The wake command looks up device hostnames in your netglance database:

netglance discover  # Scan your network and populate the inventory
netglance identify list  # View discovered devices and their hostnames
netglance wol wake <hostname>  # Now this will work

If a device isn't discovered, ensure it's powered on and responding to ARP/mDNS during the scan.

Daemon Mcp