Wake on Lan over WAN

Clocker

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Howdy all-

Have any of you gotten Wake on Lan to reliably work over the internet? I would like to bring a PC out of Sleep mode remotely, as needed. I got it to work initially but then it stopped. After some research, I found the info below posted in some forums. Seems like an ingenious solution to the ARP clearing problem but was wondering if there is anything else that works?


Assuming you've already setup WOL correctly on NIC, bios, router, given a static ip to the computer, tested it out and were initially successful doing WOL over WAN, but failed after a period of shut-down time, is because your router clears its arp table as stated above.

However, there is a KISS way to bypass that pesky cleared arp list that obviously doesn't contain your shut-down computer. No telnet, no hacking static entry in DHCP that will eventually lockup your router, no suspect firmware, no VPN, no dedicated computer required.

Although similar, this is not VPN. The caveat is you must have a printer, voip or any device with an IP/MAC address that is constantly on, then a simple inexpensive $15 hub after the router will work. NOTE, it must be a hub. A hub broadcasts to all devices connected to it, a switch will only send packets to the specific device its intended for and not the other connected devices. Set your router to port forward (Use port 9) to go to the constant active device (I have a cheap HP Combo Printer/Fax that is always on) and thus will always show up in the dynamic arp cache. Therefore the packet will not get dumped since it has someplace to go.

When you send a magic packet to the router's IP address, it will forward it through the hub to the printer, however the magic packet contains the MAC address of the computer I want woken up. According to the router, the target device for the magic packet is the printer, but the hub inside the LAN will also broadcast it to all devices, one being the hub-connected computer even though its not in the router's dynamic arp list.

Always a good idea to reserve the IP addresses for the constant on device and the computer to be woken up, if your router supports it.
 

Howell

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This is an unconventional solution that should work. Adding a static arp entry to the router would is perfect for this. Also, no need to reserve the address in dhcp, just hard code an address outside the range.
 

Clocker

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Yes, the static arp entry would be preferred but I can't figure out how to make my RT-N66U remember it. There was a configuration file I modified but the setting didn't seem to stick.
 

Clocker

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The justin montgomery solution seems simpler and more elegant. But it also seems somewhat less secure because it involves broadcasting the WOL packets to every device on my network.

The initial method using the cheap old hub seems to be more secure (to me) because the only devices that receive the broadcast message are those that are connected to the cheap hub. But this method seems to have some baggage. Using an old cheap 'dumb' hub means I will lose gigabit speed and be limited to 100mbs at most. One potential work around for that is to have two network cards in the Server I want to remote control. One NIC would be connected to the cheap hub and basically only function for WOL. The other NIC would be connected to the gigabit portion of the network for data transfers etc. If that is feasible, is it even possible to have two NICs in one machine (Win10 Pro) that get IPs from their same router and would utilized as described? If so, how is the 'work' split up between the two?
 

Howell

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If you had 2 NICs in a Windows machine and you had the gateway configured on both then the IP stack would create 2 default route entries and the IP stack would balance the traffic between them. But you don't want that. If you went this direction you would only put a gateway on the gig NIC.

It looks like indeed the ability to modify arp entries in stock firmware is limited. Are you opposed to alternative firmware?
 

Clocker

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I'm not averse to using other firmware. I've used Tomato on the past in with my old RT-N16 and it seems that Tomato/Shibby does have some settings for static ARP configuration in addition to the 'justin montgomery solution' above. I'm not sure how well they actually work though and didn't want to invest too much time in learning it.

Good news though, I made the stock Asus firmware work by finding my error when I tried it the first time.

This is the 'hack': http://www.snbforums.com/threads/static-arp-after-reboot.7969/#post-231262

The Asus Download Master service on the router is installed and temporarily enabled which allows a script to set a static ARP upon bootup. When I did it last time, I thought the Download Master service could then be uninstalled but really I was only supposed to disable it (if desired). By uninstalling it, I lost the needed functionality.
 

Clocker

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Thanks for your feedback in trying to get this solved. :)
 
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