With Glowforge "Off" it Sends 1500x DHCP Discovery Messages per Day

Our IT staff recently noticed that around 1500 DHCP association timeout errors were being logged on our DHCP server per day. Upon further review, they traced the error down to our Glowforge.

With the Glowforge “powered off”, it sends out about 1500 DHCP Discover (Option 53) messages per day.


By “powered off”, you mean powered off, as in the switch is in the off position? That seems weird… I doubt the computer is powered when the switch is off, so the probability that it’s connecting to WiFi and flooding your network with DHCP messages is pretty low. Does it still happen if it’s unplugged?



The issue persists even if the Glowforge is physically disconnected from mains, so the Glowforge itself is not sending the DHCP queries. There must be a gremlin elsewhere.

That said: are there two NICs inside the Glowforge? The errant DHCP messages appear to come from a Wisol NIC (which “appears” for a short time when the Glowforge is turned on), but our Glowforge is using a TI NIC for its normal operations.

Scan your network and see if the MAC that’s asking for DHCP responds. I’m guessing you’ve got an IP conflict. Like maybe a device that at one time had the same IP as the GF is now getting is asking for a new IP and not getting it (the DHCPs), so it’s still using that IP even though it’s the same IP that’s getting served to the GF when it powers up.


I went and checked the logs on my Router and I don’t see any unusual DHCP activity. I do see some DoS attack scans, and it looks like some of the older IP cameras I have that show exterior views around my house have been discovered. Time to retire those cameras I guess.


Since there doesn’t seem to be a problem with your Glowforge, I’m going to move this to Everything Else so the community can continue helping with your network trouble.

The DHCP Discovery messages, in a packet capture, appear to come from the MAC address previously ID’d as corresponding to the Glowforge.

Can someone from Glowforge please answer my two NICs question?

Now that they’ve moved it from Problems & Support, they are not likely to see this. They don’t generally monitor this or other non-P&S parts of the forum. You’ll be better off emailing them so you can get a real answer vs. getting the topic moved/closed without an answer to that question.

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But you still see those packets even when the GF isn’t plugged in, so it can’t possibly be the GF. I don’t think GF support can do much for you even if they’d be inclined.

You only see Discovery? No Offer/Request/Ack? If not, why doesn’t the DHCP server respond to the Discovery?

They’re only looking at the server logs? Nothing like Wireshark to sniff packets?

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No teardowns have indicated anything like 2 NICs.

Is it possible your company uses some sort of asset management tag technology?


A few things.

First, if you need to find the MAC of your Glowforge you can do the following:

  1. Reboot your Glowforge.

  2. Wait at least 30 seconds, or until the Printer Head stops moving.

  3. Open your browser and go to setup.glowforge.com.

  4. Open the Javascript Console (in Chrome, this can be found under View > Developer > Javascript Console. In Firefox, it is found under Tools > Web Developer > Web Console).

  5. Follow the Wi-Fi Setup steps until you are connected to the Glowforge Wi-Fi access point. The page will say “Connect Your Glowforge to Wi-Fi”.

  6. In the Console, paste the following code:

fetch('').then((response) => { return response.json() }).then((data) => {console.log(data.address)})

  1. This should return a bit of code that looks something like the following:

Promise {<pending>, nr@context: r}


Here’s how it looks in the Javascript Console on Google Chrome:

The second line in this response, a1:b2:c3:d4:ee:f5, is the MAC address.

  1. Exit the webpage, reconnect to your usual Wi-Fi network, and reboot your Glowforge.

As a note, your Glowforge has 2 network interfaces, each with a different MAC Address. When the Glowforge is in WiFi setup mode (button is teal and is broadcasting WiFi) the MAC address for that interface is not the MAC address for the interface that your Glowforge uses to connect to your WiFi network. The instructions above should capture the correct MAC address for you if you’re looking for the MAC used while the Glowforge is operating as a network client.


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