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Step 2 - Collect your MAC address

From the PC on which you want WOL functionality, go to the command line (Start-Run-cmd) and type “ipconfig /all.” This will tell you the IP and MAC of the NIC you want to receive the WOL signal.

It’s handy to store this information in a file you can access from the PC you’ll be using to power up the target PC. The MAC address will be the “Physical Address” in the form XX-XX-XX-XX-XX-XX. In the below example in Figure 4, the Physical Address is shown as “00-12.” I deleted the rest of it; normally, you’d see the full six sets of characters. A sample MAC looks like this: 00-01-02-55-77-B3.

Figure 4: The results of the "ipconfig /all" command

Step 3 - Download and install software

There are a lot of useful utilities for WOL. The intent of this guide isn’t to review or recommend software, but to show you how to make it work.

I use two WOL utilities, mc-wol.exe, and AMD’s Magic Packet Utility. I like the AMD Utility (www.amd.com/us-en/assets/content_type/utilities/magic_pkt.exe) as it allows for creating and saving a file of target PC MAC addresses. This comes in handy, allowing you to fire up the application, open your file, grab the MAC, and power up.

The other tool I find invaluable for network troubleshooting is Ethereal, now known as Wireshark (www.wireshark.org). These three tools are freeware and easy to use.

Step 4 - Test your configurations!

When making changes to your network, you can’t be too thorough. Make one change at a time, and test each one from controlled scenarios as much as possible. Turn off your PC while at home and test WOL to watch the PC turn on!

mc-wol.exe is a simple DOS based utility and works well over the LAN. Using another PC on the same LAN as the target PC, start up the command line and go to the directory where you saved the mc-wol.exe utility. From the command line, execute the application with the MAC as its argument. For example: MC-WOL 00:01:02:55:77:B3 Note that the command and MAC address aren’t case-sensitive, so you can skip the shift key.

You should observe the target PC powering up almost instantly upon hitting enter. If not, stop here and go back to Step 1. WOL won’t work over the WAN if it doesn’t work on the LAN. Measure, in seconds, the amount of time from power-up to boot completion. Knowing this will make the wait when you’ve sent a WOL signal easier.

Step 5 - Configure your router

There are two parts to WOL router configuration: optional and required changes. We’ll discuss the optional configurations here.

To send a WOL signal over the Internet to your LAN, you need to know your Public IP. Unless you’re paying extra for a static public IP, your ISP can change your public IP address whenever it wants, often when you reboot your router.

Dynamic DNS is a free and useful way to keep track of your Public IP address. If you have a Linksys or D-Link router, odds are that it has Dynamic DNS (DDNS) functionality. Both work with a free public website, www.dyndns.org. Set yourself up with a free account and you’ll have a fully qualified domain name that won’t change, even when your ISP changes your IP.

Enable DDNS and enter your account information into your router, and your router will keep your IP tied to your new domain name. There are other Dynamic DNS services that also work.

If your router doesn’t support Dynamic DNS, you can download a PC-based client from Dynamic DNS to allow a PC on your LAN to keep your public IP associated with your domain. However, your domain can't be updated if your IP changes while your computer is turned off.

Static DHCP is a useful router configuration for a PC that you want to work with remotely. I like this better than setting a static private IP. Static DHCP lets your PC synch with the router and get the correct DNS information, saving the hassle of configuring it on the PC. Most routers allow you to specify a MAC address and assign it an IP address. When properly configured, your PC will now always have the same IP, but get the current and correct DNS IPs. Further, your router will have the MAC address of the target PC stored in its config.

Set up your router to allow for remote login. This is a security concern, but it comes in handy while troubleshooting your home LAN remotely.

Ping is a very powerful tool that is very useful for troubleshooting. The default setting on router and PC firewalls is to disable ping or echo replies. Having this functionality enabled helps verify the reachability of your LAN and PC.

Many routers have the ability to perform simple diagnostics, including a ping test, similar to what's shown in Figure 5. If your PC firewall allows pings, it will come in handy when you’re trying to see if your PC is on or off. Familiarize yourself with this aspect of your router. It is useful to be able to log into your home router remotely and ping your target PC.

Figure 5: A router ping test

Last, if your router has a logging capability, you can use it to see if your WOL packets are hitting your router and being forwarded to your LAN. It's definitely a feature that you’ll find useful if there are issues.