If you are having trouble waking your machines, please verify that they are WOL capable, using a desktop WOL application running on the same local wired network. Suitable applications are:
Get your WOL working using one of these first. The troubleshooting section below (scroll down) will help you.
Things to remember
- WOL requires wired ethernet. The machine you are trying to wake must be hard-wired to a switch or access point. The WOL packet can be sent from a wireless device, but it must go into the target machine through an ethernet cable.
- Many machines require WOL/WakeOnLan/WakeOnEthernet etc to be enabled in the BIOS.
- Some older machines with a separate ethernet card require a special cable to the motherboard to support WOL.
- Some machines don't support WOL at all.
- Some machines require the system to be powered off in a certain way - e.g. WOL might require you do a clean shutdown.
- Laptops/Netbooks will usually require the power adaptor to be connected to accept WOL packets.
- The app requires fixed IP addresses on the LAN.
- You must get the MAC address absolutely right.
How do I find my MAC address?
- Linux/Mac: In a terminal: ifconfig -a, then look for 'HWaddr' under 'eth0' or similar.
- Windows: Start>Run, cmd <enter>. ipconfig /all, then look for 'Physical Address' under 'Ethernet adapter Wired' or similar.
How Do I Remotely Wake My Home Computer?
Remote wake up (i.e. over the internet) requires the following:
- Knowing your external IP address, or a valid dynamic dns configuration that points to your external IP address.
- Your firewall must route packets on port 9 to your machine, or send them to the broadcast address for the network. You will almost certainly have to manually set this up in your router settings.
Remote wake up (over the internet) has the following limitations:
- The glow indicators are not likely to work as they require ping which is frequently blocked by firewalls and OSs.
Remote wake-up should be validated using a web based WOL packet sending service [depicus.com] before attempting to set up the iPhone.
Troubleshooting Wake on LAN
The first thing to do is to get Wake on Lan working from within your home network. You should ensure that this works before trying anything else (such as Remote Wake on Lan using dynamic dns). If you get stuck, read on...
Wake on LAN does not work on my local network.
I’ve got the Wake iPhone app running, it’s all configured correctly, and I am connected to my access point by wifi, but when I press the wake button, the target machine just sits there...
|Is the target machine wired to your network?||You need to have a network cable between your access point and the machine you are trying to wake.||Wake On Lan only works over ethernet. Wifi won’t work.|
|Is Wake on LAN enabled on the target machine?||The low level configuration of your computer is controlled by a the computer’s “BIOS”. This is a configuration menu you can access just after power on, usually by pressing F2/F11/DEL, etc. Look for WOL/WakeOnLan/WakeOnEthernet, and make sure it is turned on and saved. If you can’t find the setting, Wake on Lan is probably not supported by your computer.||Enable WOL in your BIOS to allow the machine to keep the ethernet adaptor powered, and wake from it.|
|Are you connected to the right network?||Your iOS device must be connected to *your* access point via wifi, not the neighbours internet connection. Check that you are actually connected to the right network in settings.||You’ve got to be on the same LAN as the target.|
|Have you shut down the target machine cleanly?||Wake on LAN sometimes only works with a clean shutdown. Start up the computer and shut it down cleanly. You can tell if the network adaptor is listening because a small light next to the network connector on your machine will stay lit, even when the rest of the machine is off.||Your machine must be cleanly shut down into a state that can be woken by wake on lan. The ethernet port light tells you if the adaptor is still powered.|
|Is your computer able to wake from the state you are putting it in?||Wake on LAN sometimes only works from certain power off states. Sometimes the text next to the setting in your BIOS will describe which states the Wake on LAN will work from, e.g. “S1,S2 & S4”. For simplicity, we can assume ‘Standby’=S1,S2 or S3 ‘Hibernate’=S4 ‘Shutdown’=S5. If in doubt, try each one in turn.||To find out what power states your machine supports use: powercfg /a (windows). You need to shutdown your machine into a state that the machine can wake from. Your BIOS help screen or manual will tell you what’s possible. This microsoft article on sleep states and intel article on remote wake up may be helpful.|
|Do you have the right mac address?||Windows: Start up the target machine and click Start > Run and type “ipconfig /all”
||Check your mac address using ifconfig -a (mac/linux) or ipconfig /all (windows), and make sure it matches the setting in Wake.|
|Does Wake On LAN work using a different program?||Try downloading one of the PC applications at the top of the page. If this doesn’t work then there is probably something wrong with your setup. If a PC based application works, and the iPhone app doesn’t, please email your problem to the address on the contact page.||If alternative WOL clients won’t work either, then you probably have a hardware configuration problem, or WOL is not supported by your devicces. If everything else works and the Wake app doesn’t, contact the support email address explaining your problem.|
If all else fails, please contact iphone[at-sign]davet.org with the problem and I'll help you sort it out. I'd rather help you get it to work than leave you to write a bad review if your configuration is wrong.
The on/off status glow is not correct.
Wake on lan is working fine, but that green/red status glow is annoying because its wrong! Why do my machines show up as ‘off’ even when they are on?
|Are you on the same LAN?||Due to the way the status glow works, it cannot see the on/off status through a firewall. Most home routers have a firewall on their modem connection, so the on /off glow will only work if you are on the same wifi network as your machine.||The status indicator uses ping to determine on/off status. If you can get a valid ping response from the target, from where you are sat on the internet, then the status indicator will work. If your target machine is a home PC behind a NAT firewall, ping won’t get through, so you are out of luck. You can actually use Wake to see if certain servers are online (e.g. google.com), but do bear in mind that not all servers respond to ping.|
|Can other machines see the target machine?||You need to have something called 'PING' enabled on your target machine. This is defaulted to off in recent Windows versions, but you can re-enable ping following this microsoft article.||If you have another computer on your network, open a command prompt and type (e.g.) ping 192.168.0.6
Wake on LAN over internet does not work
Wake on LAN over my home network works fine, but when I try up to wake from a cellular connection, nothing happens.
|Have you used your external IP address?||Most internet connections use a modem/router which creates a small network in your house, but appears as only one IP address to the rest of the internet. When using Wake On Lan over the internet, you need to know that external IP address. You should be able to find this from your modem's status page, but this link will also tell you it. An address like 192.168.x.x or 10.x.x.x is not an external IP address! If you have a 'Static' IP address assigned by your ISP, then you need to use that. Services like dynamic dns e.g. dyndns.org can help you keep track of the IP address assigned to you by your ISP.||The WOL packets need to get to your LAN across the internet, so they need to be sent to your LAN's external IP, whether static or dynamically assigned.|
|Is your router port forwarding set up correctly?||You need to set up port forwarding on your router to send WOL packets to the ‘broadcast’ address for your home network, e.g. something like 192.168.0.255 (where 192.168.0 may need to be changed to match the first part of your machine's LAN IP address). If your router won’t allow you to do this, search on google for wake on lan and your router model number.||Your port forwarding needs to work while the software IP stack on your target machine is not running. This means that your target machine won’t be responding to any ARP queries, any DHCP IP leases will eventually expire, as will any previous ARP table entries in your router. You need to make sure the incoming WOL packet will be sent down the wire where your target machine is. This means either configuring your router to forward a port to the broadcast IP address for your LAN, or (better) configuring your router to forward to the broadcast mac address.|
|Does your ISP have a firewall running?||Some internet service providers (e.g. plus.net in the uk), have a built in firewall enabled on your behalf. This blocks incomming traffic on certain ports, regardless of your router settings. You may need to look at your ISP's web configuration pages to find out whether this is the case. The option you need to enable may be called something like 'home server'.||You need to let the WOL packet through all firewalls, both your own and your ISP's.|
If you are still having trouble, I recommend the following to debug your setup:
- Confirm that the Wake app is fully reliable when using it locally on your LAN. Shutdown and wake the target a few times, then for any other testing, make sure you shut down in exactly the same way.
- Run a packet sniffer such as Wireshark on a machine on your LAN, then using a service like depicus to send a wake on LAN packet to your external IP. If you see a magic packet come onto your LAN, then your ISP settings are ok and you are using the right IP address. If not, try to figure out why the packet is not getting to you (firewall somewhere?)
- Try using port 7 instead of port 9 (both on the Wake app configuration and on your router port forwarding settings). Some systems are more friendly to packets on port 7.
- Turn on the firewall logs on your router, then look for clues there after trying a few wake attempts.
Wake on lan over internet works but stops working after a few minutes of the target computer being off.
I got wake on lan working over the internet. But if I leave my machine off for a while, it no longer wakes remotely.
|Is your router port forwarding set up correctly?||See previous section.||See previous section.|
If you are still stuck please email me on iphone[at-sign]davet.org