cam_d
Level 2: Rookie

nighthawk M2 blocks printer access to LAN

I am trying to help a friend who has recently converted their home broadband to a mobile plan and was sent a Netgear nighthawk router.

Internet is fine, but he can lo longer connect to his printer from his windows 10 desktop.

The desktop has ethernet only and so connects to the LAN port on the M2.

It gets IP address from dhcp and can ping the printer successfully, but cannot find the printer using standard windows procedures.

 

The printer is connected by wifi (2.4GHz I think) and other laptops and devices on wifi (either band) can connect to the printer.  So it does not look like the mixed band problem.

All "networks" are set to private.

To check firewall issues on the desktop I have tried my own laptop which I know has no firewall active and no 3rd-party AV software.  I can scan for the printer easily over wifi, but it will not find it if my laptop is connected via ethernet.

The printer offers a web interface on port 80.  I cannot access it even using a browser when plugged into the wired LAN, but wireless is fine.I can also set up my phone (5GHz) with a port 80 server and it has the same problem - can be connected by wireless but not wired.

So clearly the router is intentionally blocking TCP traffic between the wireless segments and the wired. I have been through the entire web interface on the M2 and cannot find any suitable setting for fixing it.

 

I could modify nft or ebtables rules if necessary, but is there even any root login to the system?

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12 REPLIES 12
SteveW_52
Level 22: Superhuman
Level 22: Superhuman

Re: nighthawk M2 blocks printer access to LAN

Is the ip address for the ethernet connection on the laptop in the same range as the other router wi-fi addresses?

 

The ethernet port on the Netgear M2 (and other) modems seems to be unmanageable from the GUI..   try a wi-fi dongle in the laptop and see if that works..

Stevo 52
Too many devices, probably an addict :-) also a tinkerer and developer of stuff..
Not with Telstra, just another customer like you!
cam_d
Level 2: Rookie

Re: nighthawk M2 blocks printer access to LAN

yes, the wired and wireless segments are the same subnet. Ping scanning the subnet reveals all devices.

The wired connection has no problem accessing the web interface of the M2 router.

 

I have no wifi dongles, and I can't really see the point - we know wifi works.

If we want to later connect other wired-only devices via a switch it is also not a solution.

SteveW_52
Level 22: Superhuman
Level 22: Superhuman

Re: nighthawk M2 blocks printer access to LAN

The point of trying a wi-fi dongle, was to make sure the networking setup of the desktop is OK and you can do everything you want to..  just eliminating other possible issues..

 

I have had trouble with the Netgear 5 G modems in the past when trying to connect a device via the ethernet port..  I never had the time to resolve the reason for it, but did find using a wi-fi AP seemed to work OK, even providing the required ethernot points. But just using the M2 ethernet port for a single device didn't seem to work as I thought it might..  it was like the modem expected it to be an alternative WAN port..  I never got a valid DHCP IP address configuration assigned by the modem when I tried connecting that way..

 

The user guides for the M2 and M5 are very light on detail of that ethernet port. There is another post currently being discussed but for  an M5 setup.. there was a link to a Whirlpool post about the issue and possible solution (which I haven't tried as I don't have either of the Netgear 5G modems on hand right now.

Stevo 52
Too many devices, probably an addict :-) also a tinkerer and developer of stuff..
Not with Telstra, just another customer like you!
cam_d
Level 2: Rookie

Re: nighthawk M2 blocks printer access to LAN

My working hypothesis is that it has something to do with the dual function of the ethernet port. They would need a lot of changes to the firewall rules (as well as everything else)  when switching the port between LAN and WAN mode - I suspect they left a few wrong rules in place for LAN mode. Although I can't think of a configuration that would readily lead to this.

SteveW_52
Level 22: Superhuman
Level 22: Superhuman

Re: nighthawk M2 blocks printer access to LAN

I thinjk you are right, but there are not a lot of settings available in the GUI to address the issue - I gave up sadly, not my usual thing to throw my hands in the air, but that modem frustrated me..  sometimes things (especially Telstra things? ) are simplified beyond usefulness..

 

Have a look at this other thread for the M5, with similar needs..M5 thread . Hope it helps..

Stevo 52
Too many devices, probably an addict :-) also a tinkerer and developer of stuff..
Not with Telstra, just another customer like you!
cam_d
Level 2: Rookie

Re: nighthawk M2 blocks printer access to LAN

yes, definitely sounds familiar. thanks for your time.

Mkrtich
Level 21: Augmented
Level 21: Augmented

Re: nighthawk M2 blocks printer access to LAN

Hi - curious, if the PC is connected to the Netgear M5 centre USB-C port with the included cable per the User Guide instead of the Ethernet port, is the printer visible in Windows and function correctly. Maybe the LAN/WAN port is used for IP Passthrough or Data Offloading applications only. There is an Ethernet Standby setting that in Default, turns off the port if unused after 2 mins to save the battery which may also be interfering with matters - it can be Disabled.

cam_d
Level 2: Rookie

Re: nighthawk M2 blocks printer access to LAN

ethernet standby had already been disabled.

In IP passthrough and data offloading the M2 should not be still replying to dhcp requests with a local IP address. It is functioning like a LAN port, just badly.  If it is in data offloading mode then having it respond to web interface requests is a major security flaw.

The owner already has the workaround of placing PC and printer close enough that they can connect by USB cable. And the USB-C port is the power port, so not a solution of any sort.

He also uses it occasionally for travel (without the desktop), so the alternative solution of IP passthrough and a better router is not convenient, as it would require reconfiguring the M2 each time.

My main complaint is that it is sold by Telstra and Netgear as suitable by itself for home-networking, when clearly it has significant limitations.

SteveW_52
Level 22: Superhuman
Level 22: Superhuman

Re: nighthawk M2 blocks printer access to LAN

I think the assumprtion of the intended market for these Netgear 5G modems, is for Wi-Fi networking only, on the basis that it is a mobile device after all.  I think the less than full explanation of the ethernet port is a pointer to 'expected use'.

 

I have used, in the past, powered usb C hubs to allow power to a device, and usb ports for other devices to be attached. 

Stevo 52
Too many devices, probably an addict :-) also a tinkerer and developer of stuff..
Not with Telstra, just another customer like you!
Mkrtich
Level 21: Augmented
Level 21: Augmented

Re: nighthawk M2 blocks printer access to LAN

Yes, the M2 is marketed as a Mobile Hotspot but tempts people with other claimed capabilities as a home solution. The USB-C port appears to have the capability for a 'Charge Only' setting for power adapter connection or 'Charge + Tether' when connected to a PC to do both functions simultaneously. Just thought it would be interesting to see if that somehow allowed printing to work from the PC to the wireless printer. It's annoying when things don't work as they should. 

cam_d
Level 2: Rookie

Re: nighthawk M2 blocks printer access to LAN

In this case it was sold by the Telstra shop as a replacement for a less than ideal home nbn system, with the advantage of taking it travelling.

All up, I think it has worked out as a very good solution for that family, but if you add up the initial frustration of him trying to get it working, then 2 hours of another friend Dave's time, then the time I put into it, all for some stupid oversight on Netgear's part...

SteveW_52
Level 22: Superhuman
Level 22: Superhuman

Re: nighthawk M2 blocks printer access to LAN

Unfortunately, Telstra staff don't always know all the in's and outs of the products they sell, especially any possible limitations...  support staff especially..

Stevo 52
Too many devices, probably an addict :-) also a tinkerer and developer of stuff..
Not with Telstra, just another customer like you!

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