If you have the need to wake up machines on your local LAN from the outside, there are a few steps you need to take to get it working with OpenWRT (12.09)

  1. Select an unused IP address (which you are certain will never, ever be used). I will be using in the following
  2. Log into OpenWRT and go to System → Startup → Local Startup (the text input at the bottom of the page) and add this line above exit 0: ip neigh add lladdr ff:ff:ff:ff:ff:ff nud permanent dev br-lan
  3. Save (or Submit depending on the theme used)
  4. Go to _System _→ Software and verify the package ip is installed. If not, do so.
  5. Go to _Network _→ Firewall → Port forwards and add a new rule like this:
    forward.png (select custom to enter the internal IP address).
  6. Save and apply
  7. Reboot the router

That’s it. Now wake on lan should work from the WAN (Internet) as well.

This is what it looks like in the WoL Wake On Lan Wan Android app: