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jenniferrr's profile

New Member

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26 Messages

Sunday, April 10th, 2022 1:29 PM

Ethernet - Router not assigning IP addresses to some devices.

Hi there, 

I have ATT Fiber, and everything was working fine until two days ago. Now two computers in my home (1 Mac and 1 Windows) will no longer connect via Ethernet and receive the error "Ethernet has a self-assigned IP address and will not be able to connect to the Internet." - both computers will connect wirelessly, but I need them connected via Ethernet for my work. 

Other wired devices to the network work fine, wireless is  the wall jack is working fine, the computers are fine (Contacted support for each after Customer Support told me it was an issue on my computer). 

When I first notified support I was sent a new router, but the problem persists. I asked if they could update router settings, but was told the connection was working fine and the issue was the ports on my computers. Both devices are brand new and working fine. Confirmed this is a router issue with both of my computer manufacturers yesterday. 

Each of the computers are connected via an internet switch, which was installed by the ATT Tech who installed the service. Service wires are about 5 months old as this is a new home. (Just trying to give all the details here) 

Steps taken to troubleshoot: 

New router installed

Renewed DHCP Lease 

Tested Wall Jack 

Tested other ethernet connect devices (working normally) 

Troubleshoot with both windows and mac tech team to verify devices are operating fine. 

*NOTE Computer will connect via Ethernet if manual IP address is entered, but need correct one to work properly 

Can someone tell me what settings in the router need to be adjusted to get these working via ethernet again? 

New Member

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26 Messages

2 years ago

One is a TL-SG105 and the other is a TL-SG108.

ACE - Guru

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9.9K Messages

2 years ago

Ok, thanks, neither one is a managed switch that could have settings causing this so that's good and bad.  Bad in that there goes one other possible explanation. 😁

New Member

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26 Messages

2 years ago

The mystery continues!!! :D 

ACE - Guru

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9.9K Messages

2 years ago

Unfortunately.  I mean the obvious fix is just to assign static IPs to the computers and be done with it.  But the fact that this setup worked fine for some period of time is what's intriguing.  Since the Windows machine works ok if you take all of the switches and wall plates and Ethernet cables out of the equation it definitely seems all that stuff in-between is the cause (or it's giving the BGW fits).

I'm not a Mac guy but it seems like there's a fairly commonly suggested fix for that specific OSX error message, but I suspect you already looked at that.

I dunno, maybe my esteemed colleague @JefferMC, who has waaay more knowledge about network layers and their interactions than I do, might have some ideas.

ACE - Expert

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35.8K Messages

2 years ago

From what I'm reading there are multiple issues that appear to be related to going from the remote location through the house wiring, through the switch, to the BGW320.

1) It appears that DHCP is failing on two devices, because you're getting self-assigned IPs

2) It appears that even if you manually assign IPs, that IP traffic still doesn't work. 

If you bypass the switch and house wiring, the PC works directly connected to the BGW320.  You aren't able to test the Mac this way.  

Hm...  Puzzling.  

 

In reading through this 3 page thread, I'm unclear about some things.  These are things I'd like to hear the answers to.  If you've already tested them, let me know, if not, could you test them?

1) If you use the house wiring but not the switch, does the device work?

2) Can you bypass the house wiring and connect the PC directly to the switch (vs. the BGW320), does that work?

3) Are the PC and Mac connected to different switches?  Can you switch the switch each is connected to?  What happens?

4) With manually assigned IPs for both devices, can you PING between the two?

5) What information shows in the Windows Ethernet adapter properties when connected to the Switch via the house wiring?  Is that different when connected directly to the Gateway?

New Member

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26 Messages

2 years ago

Thanks for your time and help! 
I’ll try to answer the best I can: 

1) If you use the house wiring but not the switch, does the device work? 

- yes, it worked at a different wall jack, (which ran through a switch at the main connection which runs to the router). It also works intermittently at the wall jack in the room where both computers are located. It works when plugged into the direct house wiring which leads to the router. 

2) Can you bypass the house wiring and connect the PC directly to the switch (vs. the BGW320), does that work? 


- Do you mean connect the switch to the BGW abs then connect the pc that way? 

3) Are the PC and Mac connected to different switches?  Can you switch the switch each is connected to?  What happens?

- They are connected to the same switch. When I try a different switch, the issue persists. 

4) With manually assigned IPs for both devices, can you PING between the two?

- I am not sure how to go about setting this up, my apologies! 

5) What information shows in the Windows Ethernet adapter properties when connected to the Switch via the house wiring?  Is that different when connected directly to the Gateway?

- IP assignment: Automatic (DHCP)

   DNS suffix search list: attlocal.net 

   
it also contains driver version, description, etc, is there anything specific with the information that you are looking for? 

All properties remain the same across different setups. 

ACE - Expert

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35.8K Messages

2 years ago

1) Thanks

2) I think you brought the PC to the BGW320 and connected directly to the BGW320 and it worked.  I was wondering if you connected the PC to the switch directly (like the BGW320, not through the house wiring) does it work?

3) Thanks.

4) If you have them both with manually assigned (or self assigned addresses, that's okay too), note the IP address of the mac, and go to the PC, open a CMD window, and type "PING " followed by the IP address of the MAC.  The MAC has a PING tool (somewhere), you can open it up and type the IP address of the PC and do a PING that way. 

5) What I was looking for is what you get when you click on the network in the taskbar (which gives you Network & Internet settings), then click the Properties button under Ethernet, scroll down to the section labeled properties (has link-speed, etc.) and get a copy of that information (screen shot is fine).

My operating theory of the moment is that there's something marginal about the home wiring that the BGW320 is able to overcome that the switch is not.  Which is very strange; usually it's the other way around.

New Member

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26 Messages

2 years ago

Happy Sunday! 

1) I think you brought the PC to the BGW320 and connected directly to the BGW320 and it worked.  I was wondering if you connected the PC to the switch directly (like the BGW320, not through the house wiring) does it work?

 

- Want to make sure I understand this correctly, do you mean connecting the switch to the BGW directly and then connecting the PC to the switch? 

2) Ping Tests: Sadly both failed when on manually assigned IPs, BUT I'm not sure if I was able to assign them correctly for my PC due to it being my work computer and admin settings. The IP address (192.168.1.254) was showing on the DNS server in properties: 

That is a screen shot of the properties when connect via ethernet only, fixed allocation, and WiFi disabled. 
Regarding my home wiring, it is about 5 months old and didn't have any issues until now. Everything else seems fine. 
Not sure what could happen overnight to make these two computers have this issue. 

(edited)

ACE - Guru

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9.9K Messages

2 years ago

I think JefferMC was essentially trying to eliminate as much of the house wiring as possible, so like this set up in the same room as the BGW....

The ping test was suggested after you assigned static IP's to the two computers.  The 169.anything address shows that the PC was trying to get an IP assigned to it, and failed.  So it's not going to see anything  with that address.
Not meaning to laugh at you; you've been great and I admire your tenacity to see this through.  But I do find it somewhat amusing that many people have this notion that if some tech device was working yesterday and nothing has changed, it should still be working today. 
I'm sure you wouldn't be surprised if you turned on a light switch today and the light that worked yesterday didn't go on today, you'd just conclude the bulb had burned out.  Stuff happens, switches have components that could fail at any moment.  You've got at least one switch hanging, suspended only by the Ethernet cables.  You could have developed a bad connection on one of the eight conductors in that cable from the strain.  Critters could have chewed through the wiring in the walls.  Lots of possibilities, which of course are making this even more difficult to troubleshot than it already is by having to do it remotely.

(edited)

New Member

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26 Messages

2 years ago

Gotcha with the IP address info. I tried to ping the assigned IP address I allocated through the ATT router settings and understand if that wasn’t correct. 


Just a heads up, the Switch isn't just hanging by the Ethernet cords, it is secured to the wall. 

I really appreciate everyone’s time and effort trying to help me figure this out. It’s very kind of you all. 

(edited)

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