Oppo tech support needed

"shop-teacher" (shop-teacher)
10/14/2019 at 23:02 • Filed to: Tech support

I have Comcast internet coming in, the modem is one I own, an Arris CM820. If I directly connect a device via hardwire , I have internet. If I connect either of my wireless routers, no signal comes out the other side. Either wirelessly or through Ethernet cables. The routers are a TP Link AC1750, and a Netgear N150. I tried replacing the patch cable going between the modem and the router.

I am completely at a loss. HALP!!!

DISCUSSION (30)

Phyrxes once again has a wagon! > shop-teacher
10/14/2019 at 23:14

So ethernet to a PC from the modem works, nothing else?

Presuming all the cables are good, are you getting connectivity lights on the routers when you plug them in to the modem?

If you plug the router into the PC directly like when doing a set up does it work as expected?

Full of the sound of the Gran Fury, signifying nothing. > shop-teacher
10/14/2019 at 23:17

I had this exact problem last year. I called out the tech and he couldn’t understand it and threw up his hands and basically said to live with it. I asked him why he didn’t try swapping out the modem with the spare that he brought. Lo and behold, that fixed the problem. Why he didn’t try the obvious and logical thing without me having to prompt him to do so I may never understand...

Future Heap Owner > shop-teacher
10/14/2019 at 23:23

Do you know how to check what your local network IP address is on your computer? Not the external IP address you’d get by going to a website that told you your IP address, but the IP address that your computer’s network hardware is assigned.

I don’t think it’s typical to be able to plug a computer in to a modem and get internet, so my guess is that your modem is configured to manage the network like a router , so when you plug the router in, they both want to manage the network and nothing works. Checking what IP your computer gets when plugged directly into the modem will determine whether or not the modem is managing the network.

I’m guessing that you had a WiFi network set up before, so what’s new in this scenario? The modem?

NojustNo > shop-teacher
10/14/2019 at 23:24

Gotta mention it - make sure the cable is plugged into the”internet” port on the router. Then restart the modem and see if you get internet.

Future Heap Owner > NojustNo
10/14/2019 at 23:26

Sometimes labeled “WAN”

shop-teacher > Phyrxes once again has a wagon!
10/14/2019 at 23:27

Yes.

The link light on the modem is orange and flashing. The lights on the router are all on.

Yes

Future Heap Owner > Future Heap Owner
10/14/2019 at 23:29

On the TP Link, it seems to be labeled “LAN4/WAN”, and it’s the one closest to the middle antenna

Kinja'd!!!

shop-teacher > NojustNo
10/14/2019 at 23:38

It is

shop-teacher > Future Heap Owner
10/14/2019 at 23:39

It is

facw > shop-teacher
10/14/2019 at 23:43

What status lights are you getting when you have the router connected to the modem ? On the modem you should have a solid green “Online” light and green or yellow “ Link” light that may be solid or flashing.

On the TP Link router, it looks like you should have the “planet” icon lit up at least. On the N etgear the Internet light should be on.

Assuming it looks like thing are connected, the next step is to connect to your router with an ethernet cable (since wifi seems down? do you see any signal?). Hopefully when you connect, you’ll get an IP. Try connecting to your router (probably at http://192.168.0.1, http://192.168.1.1, or http://10.0.0.1, but it probably lists the default on the label on the bottom).

If you can connect you may be able to see what is happening with the router (it’s probably also possible to reach the modem page).

If you can’t connect, I’d try a hard reset on the router before messing with anything else, since it gets more involved.

It seems really suspicious that both your routers don’t work, but I’m not sure why that would be (sorry to be so basic, but you are connecting to the internet (WAN) port on the router and not one of the switch ports right?) . In the old days ISPs would lock modems to only serve specific MAC addresses so you had to clone a MAC, but I don’t think that’s been a thing for 15 years or more, and certainly not from a big player like Comcast.

someassemblyrequired > shop-teacher
10/14/2019 at 23:47

I seem to recall something about putting the router in bridge mode to use your own router when we had Comcast.

More details here:

https://www.xfinity.com/support/articles/wireless-gateway-enable-disable-bridge-mode

shop-teacher > Future Heap Owner
10/14/2019 at 23:50

No, I don’t. My understanding of this stuff is tenuous at best.

It was my TV I plugged in directly, and it was able to stream Netflix. My actual computer is 2 floors away, and was connected through both of my routers Daisy chained together. I know, wonky setup, but it worked for me for years.

So here is what changed. We had AT&T internet for a couple years, and it went out on Saturday. They diagnosed it as a bad modem, and said a replacement would be sent to me Tuesday. Sunday I remembered I still had my old Comcast modem in the basement, so I checked with them, and they were able to get me running immediately, so I signed up with them, and cancelled at&t.

My setup for years has been the modem feeds the TP link router, which feeds an Ethernet cable to my first floor tv, and another Ethernet cable to my attic. The net gear router feeds an Ethernet cable to my 2nd floor tv, and my desktop.

That was all still working again until this afternoon. W orking with Comcast, they were showing the modem having a signal, so I tried directly connecting my TV, which worked fine, and proved my routers were the problem.

First I tried power cycling the TP link, then I tried putting the Netgear in it’s place, then I tried replacing the patch cable between the modem and the router

Now I am lost.

shop-teacher > facw
10/14/2019 at 23:55

The link light on the modem is flashing orange. The planet icon on the TP link was on, and the Netgear router,when I put it in its place showed these lights

Kinja'd!!!

The one that shows off in that pic was flashing blue, and the power light was alternating green and orange.

Yes, I have the internet feed plugged into the wan port :)

Nibby > shop-teacher
10/14/2019 at 23:56

this solution would work but it’s complicated

you can inst al l DD-WRT firmware on the AC1750and set it up as a client bridge if the router’s built in firmware doesn’t let you do it already

shop-teacher > Nibby
10/14/2019 at 23:58

My understanding of this stuff is tenuous. I’m a good cable plugger, but I honestly have no idea how to, “i nstall DD-WRT firmware"

facw > shop-teacher
10/15/2019 at 00:01

That’s probably ok then. Were you able to get to router’s web page? Does the PC connected to the router have a real IP address? Assuming Windows 10, what do you get if you go to the start menu, type “ network” and select “View your network properties”?

facw > shop-teacher
10/15/2019 at 00:10

I think you don’t want to do that. Especially if you can’t even get on the router in the first place (nothing wrong with DD-WRT, but it doesn’t seem like the solution here, especially at this point).

Future Heap Owner > shop-teacher
10/15/2019 at 00:12

Do you have a laptop or PC available? What OS & version is it running?

shop-teacher > facw
10/15/2019 at 00:15

So, my PC was Daisy chained through this and another router. It's two floors away. I can bring my work laptop home tomorrow, and try connecting that to it. I have no idea about it's real IP address. It is windows 10.

shop-teacher > Future Heap Owner
10/15/2019 at 00:17

I will bring my work laptop home tomorrow. It's a Windows 10 machine. What would you recommend for my next trouble shooting steps?

Future Heap Owner > shop-teacher
10/15/2019 at 00:26

Plug that in directly to the modem, confirm internet works, and then find out the IP address that the laptop has: https://www.groovypost.com/howto/find-windows-10-device-ip-address/

If it matches 192.168.x.y or 10.x.y.z, then the modem is managing the network and that is why your routers are unhappy. Look on the internet for the manual for your router (or grab it if you have it on hand) and configure it to be in bridge mode.

If the laptop’s IP address * doesn’t* match what I put above, then the modem is already in bridge mode, and I have no idea why your routers are unhappy. Maybe a hard reset will fix them? Most routers can be hard reset with the 30-30-30 method: hold reset button down with the power on for thirty+ seconds, then (while still holding the button down) unplug the power adapter from the router and leave it unplugged for thirty+ seconds, then plug the power back in while still holding the button for at least thirty seconds more.

shop-teacher > Future Heap Owner
10/15/2019 at 00:28

Thanks! I will report back tomorrow!

XJDano > shop-teacher
10/15/2019 at 09:29

Did you read the part in the instructions? The part in fine print that says shake well before using, or the rinse and repeat, or do not recharge disposable batteries.

shop-teacher > XJDano
10/15/2019 at 10:26

Thank you, that’s very helpful :P

shop-teacher > Future Heap Owner
10/15/2019 at 10:36

In my dither last night, I forgot that my work laptop was at my house (it usually isn’t). I connected it this morning, and I do indeed have internet service.

Which one of these is my IP address?

Kinja'd!!!

When I downloaded my modem’s manual, the directions stop at Windows 7, and it doesn’t even mention my condition of the link light flashing orange as a possibility :/

Future Heap Owner > shop-teacher
10/15/2019 at 14:38

That would be the IPv4 address. It doesn’t match those patterns I posted, so my hypothesis is falsified.

I would try hard resetting the routers and seeing if that does it, but I don’t have a specific hypothesis. The only other thing that comes to mind is maybe you are actually connected via the routers, but DNS is messed up, so while you could make a connection based on IP address, going to websites doesn’t work. But I’m not sure how to test that on Windows. I could look it up tonight

shop-teacher > Future Heap Owner
10/15/2019 at 15:11

Out of desperation, I have a new modem being shipped to my house by end of day. I’m bringing my work laptop home to try and keep figuring out what the deuce is going on.

Thanks for your help! If you come up with anything else I can try, I’m all ears.

shop-teacher > Future Heap Owner
10/15/2019 at 19:21

The hard resets worked! I’m back in business. Thanks for teaching me the 30/30/30 method, because this thing was totally borked!

Future Heap Owner > shop-teacher
10/15/2019 at 19:58

Glad to hear it!

shop-teacher > Future Heap Owner
10/15/2019 at 22:08

I really appreciate your help. Once again proving, this place is the best!