Wake on lan agent not working

[roberto21350]

The agent service on the pc always on in the remote lan used to work fine. Now it stopped working: the process does not start and refuses to start with the error 1053: the service did not respond...in a timely manner. I don't know if this is due to some windows 11 updates or other reasons, but it does not work. Any suggestion?

[roberto21350]

I have un update on this, even though it seems that the subject is of no interest. Mysteriously, without doing anything, the agent runs again (maybe some other windows update). However, wakeonlan does not work. It seems that no magic packet reaches the agent. Using the listener, It complains about the port 9 (an attempt was made ...etc). The help document suggests to disable "simple tcp/ip", but it is already disabled. Is there something wrong with the fritzbox 7590 router?

[roberto21350]

Is it possible to have agent listen on a port other than 9?

[basildane]

From the agent page:

By default the application forwards port 9 to 255.255.255.255. However, you can optionally change the ports or which interface it listens on. You can also change the broadcast ip and port. These items are defined by default in C:\ProgramData\Aquila Technology\Agent\config.xml

A config file might look like this

<?xml version="1.0" encoding="utf-8" ?>
<agent>
  <listen>
    <port>9</port>
    <address>192.168.0.8</address>
  </listen>
  <send>
    <port>9</port>
    <address>255.255.255.255</address>
  </send>
</agent>

Your topic is definitely of interest, but sadly, we are pulled in many directions and its hard to find time for this project anymore. I apologize for that but its out of my control.

So, let's start at the beginning.
I assume you have configured your router to listen on port 9 and forward traffic to your Agent service?

The first thing I would do is simplify and troubleshoot. Do you have Wireshark installed?
I would run Wireshark on the agent and watch as you send a test WOL packet. If no packet arrives, we know the problem is in the router or your internet service. It's completely possible your ISP blocks low ports. Yes, you can change the listener to use any port.

It's worth saying, I have a better suggestion. Use a VPN instead. This will solve many other problems besides just WOL.

[roberto21350]

Thanks for your attention. However, I am a little confused: how do I change the port for the agent? At the moment you start the service by running wolagent.exe without parameters, so how do you specify the port? ( something like wolagent,exe /port=xx?) Assuming you change the .xml file, do you have to regenerate the executable? sorry for the naive questions, but I am not THAT knowledgeable in the matter...
I don't have wireshark, I can try... but the problem seems to be the port 9. Also wakeonlamonitor.exe refuses to connect to port 9, (bind error, permission denied,. code 10013). I definitely know that the packets do arrive to the remote LAN: if I open port, say 5000, to the shutdown pc and then use that port instead of 9, the agent does not get involved, but the pc wakes up...
I am studying fritzbox wireguard. Maybe you are right, vpn is the way to go.

[basildane]

Stop the agent service.
Edit the file C:\ProgramData\Aquila Technology\Agent\config.xml
Change the LISTEN port to whatever you want.
Start the agent service.

But, I recommend testing with wireshark to see what the problem is, rather than blindly changing parameters when we don't know what the problem is.

[basildane]

I am not familiar with wakeonlanmonitor.exe. Where did you get that?
Does it still refuse to connect if you stop the agent service? Because agent will bind to that port by default. That's normal.

[roberto21350]

It will take a while for me to understand how to use wireshark. In the meantime, I ran a quick test, and I am more disoriented than before. Following your suggestion, I changed the port for agent to 5555, verified that the port was properly assigned via netstat -ab, and tried to wake up a pc sending the packet to this port. Nothing happened. So I opened port 5003 to the sleeping pc and sent the packet to this port. The pc woke up immediately. Now, if the packet gets to 5003, there is no reason why it should not get to 5555. If it gets there, why does the agent not forward it to the proper mac?
Moreover, the listener linked to 5555 or 5003 does not display any packet. I am ready to give up.

AS for the wake-on-lan monitor, I found it here
https://forums.ivanti.com/s/article/How-To-Test-Wake-on-LAN-Wake-on-WAN?language=en_US
but the result is the same as your listener: no packets displayed. I really don't understand.
Thank you a lot for your patience,

[basildane]

it might help if I explain the purpose of Agent. WOL uses an unusual packet type called a "broadcast packet". Broadcasts are not directed at any one device. They can't be in this case, because the device is probably off and therefore doesn't exist (as an IP address) on the network. So, we send a specially crafted packet to the entire subnet which contains the MAC address of the machine to wake up. Your sleeping computer should be listening, and sees the message that has it's MAC address in it, and wakes up.

That's all fine, except you cannot send a "broadcast packet" over the internet. But you can send a standard UDP port 9 packet over the internet, except that won't wake up the machine. This is what Agent is for. It's extremely simple. It just listens for an incoming WOL packet, then it RE-transmits it inside your network as a Broadcast Packet. And that should get it to your sleeping machine to wake up.

WOL is typically on port 9, but it does not have to be. So, we configure your router to port-forward a port of your choosing, to the agent. The agent sees the packet and broadcasts it on your LAN. Then your computer wakes up.

You are right to be confused. It's a mess isn't it?

So, you have WOL working on the remote machine. That's half the battle.
Next, we need the agent computer to be able to wake it up.
Then we need your router to forward packets to agent, and agent to forward them to the broadcast.

Then it should work from the internet.
One step at a time...

[basildane]

Look at the example config.xml. The Send address is 255.255.255.255. That is the default BROADCAST address in your local network. You cannot send WOL to a specific IP address.

[roberto21350]

Thanks, but still something is not clear. In my test, I sent the SAME packet first to port 5555 (where the agent should have been waiting) and then to port 5003, open only to the sleeping computer: the only difference is the port number. In this second case, the packet did wake the computer, but you say that that "standard UDP port 9 packet over the internet, won't wake up the machine" : but it did, without any intervention of the agent. It looks like the presence of the MACaddress in the packet is enough to trigger the waking process in that machine.
So the situation at the moment is:

• the WOL packet sent by Aquila Wake-on-lan to the port of the sleeping computer does wake it without problems
• the same packet addressed to the Agent port (same MAC address of the former one, of course) has no effect. Since the Agent is running in the server pc (the one that is always ON), this implies:
• EITHER packets do not get to Agent port
• OR the agent does not recognize the packet;
• OR the agent is not listening
• OR the agent does not work (we can exclude this, since the agent did not change and was working before)

I am not sure, but filtering wireshark on port 9 (agent port, filter: udp port 9) I cannot see any packet...

Again, thanks a lot for your interest and patience.

[basildane]

OK, let's look at that.
On the Agent, how do you have it configured? (config.xml)

On the client program, you must configure it to send the packet DIRECTLY to the Agent computer IP or name, and port, as described here: https://wol.aquilatech.com/agent/

3 things. 1. Send to the Agent IP. 2. The port must match what is configured on the Agent. 3. The MAC address of the device to wakeup.

Finally, running Wireshark on the Agent server will let us see if the packet has arrived at the Agent server.
If you have trouble understanding Wireshark, I will give you step by step. (It's worth learning it, great software)