Internet only working on one device after activation (Xfinity)

[KingMoogle]

Hello hello!

So I recently bought 2 modems. Arris Surboard SB8200 and the Netgear CM1000.

I went through the activation process both with the automated system with the CM1000, and after that bricked, I did the phone activation with the Arris SB8200.

 

The issue I'm having, is that the internet ONLY works on the device used to activate the modem with xfinity.

I called in, they resent the activation signal and this time I tried it on my other computer, and then the internet only worked on that computer and nothing else.

Game consoles, wifi-router, other computer, nothing. It will absolutely only work with the ONE device used to activate the xfinity service through the modem.

 

It does the same thing on both modems. So of course I thought the issue is with xfinity, called in and spoke with 2 reps. Neither could figure out what the issue was.

 

I have everything hardwired through a nighthawk switch (I've also tried my basic netgear switch as well)

I've also tried connecting to each device without either switch, same situation.

I've tried multiple ethernet cables, though it's obvious this isn't the issue as the internet works perfectly fine, just on that one device used to activate it, so even if i take the already working internet and connect the modems ethernet to a different computer, it will not work. it see's the modem but never identifies the network. "Unidentified network-No Internet".

 

I wanted to know if anyone else has been having this issue?

[Donut417]

9 minutes ago, KingMoogle said:

wanted to know if anyone else has been having this issue

Im going to go out on a limb and assume that you have booted up the modem, then booted up the router, then booted up your computer? 

 

I know for a fact that Xfinity does IP leases via DHCP based on the Mac address of the device connected to your modem. Meaning, that the modem would need to be rebooted and the whole DHCP process would need to happen again so you could get a new IP for the router. Another option to try is MAC address cloning. You can make your router have the same Mac address as the computer you activated the service on. If your router supports that, it could work, but it shouldn't be necessary. 

[KingMoogle]

2 minutes ago, Donut417 said:

Im going to go out on a limb and assume that you have booted up the modem, then booted up the router, then booted up your computer? 

 

I know for a fact that Xfinity does IP leases via DHCP based on the Mac address of the device connected to your modem. Meaning, that the modem would need to be rebooted and the whole DHCP process would need to happen again so you could get a new IP for the router. Another option to try is MAC address cloning. You can make your router have the same Mac address as the computer you activated the service on. If your router supports that, it could work, but it shouldn't be necessary. 

I booted the modem, let that connect, I then plugged an ethernet into my router from the modem, plugged in power, turned it on and it would not get an internet signal.

I logged into my router from my desktop to check, and it sure enough said no internet connection. 

 

I even tried plugging directly into my nintendo switch from the modem, it also saw no internet connection even though it saw that it was plugged into an ethernet port.

[Donut417]

2 minutes ago, KingMoogle said:

I booted the modem, let that connect, I then plugged an ethernet into my router from the modem, plugged in power, turned it on and it would not get an internet signal.

I logged into my router from my desktop to check, and it sure enough said no internet connection. 

 

I even tried plugging directly into my nintendo switch from the modem, it also saw no internet connection even though it saw that it was plugged into an ethernet port.

In your routers settings make sure that under the internet tab your connection is set to auto or DHCP. 

 

Did they try to remove your modem and re add it to your account? Just pulling solutions out of the air. It almost sounds to me like its not fully activated. 

Also your only using one of the ethernet ports on the back of the modem, right? 

[KingMoogle]

12 minutes ago, Donut417 said:

In your routers settings make sure that under the internet tab your connection is set to auto or DHCP. 

 

Did they try to remove your modem and re add it to your account? Just pulling solutions out of the air. It almost sounds to me like its not fully activated. 

Also your only using one of the ethernet ports on the back of the modem, right? 

Yes I'm only using one.

So I contacted Arris, and they had me reset the modem:
disconnect all except for power, hold reset for 30 seconds, plug in coaxial cable, wait for everything to go solid, then plug in ethernet cable to a different computer, and somehow now only THAT computer (the one im continuing this thread one) is working.

I tried plugging into my msi laptop that I began this thread on and it just says unidentified network no internet now.

So now im hella confused. And yeah everything is set to DHCP as far as I know.
The modem is at it's default settings, especially after the rest I just did.

 

Actually, not that I've looked through every tab. Nothing says anything about DHCP.

And it does not allow me to change nearly anything, it's a very basic layout and even the "Advanced" tab only gives me one option, to enable a function called "LAG" by Arris for pair bonding.

 

So all in all, what I've found out now is that resetting the modem and connecting one device lets THAT device connect to the internet, and nothing else.

 

[Donut417]

1 minute ago, KingMoogle said:

Nothing says anything about DHCP.

And it does not allow me to change nearly anything, it's a very basic layout and even the "Advanced" tab only gives me one option, to enable a function called "LAG" by Arris for pair bonding.

Thats because on the modem those are not settings you need to worry about. The modem will connect what ever way the ISP needs to. Comcast issues both firmware and config file updates periodically, the ISP is actually the only ones that can issue any type of updates when it comes to cable modems. The LAG function is used if you needed to do more than 1 Gbps, some cable modems have like 4 ports. But you connect all of them to the same router and some how some way, you should get faster speeds, theoretically. However, most ISP's dont offer above 1 Gbps on coax yet. 

 

3 minutes ago, KingMoogle said:

So all in all, what I've found out now is that resetting the modem and connecting one device lets THAT device connect to the internet, and nothing else.

Thats strange. The only thing you should have to do is rebooting the modem after you connect a new device. Outside of that, nothing else needs to be done. What you might want to try is reseting the modem and connecting the router as that one device and see what happens. 

 

If none of that works, then you might want to RMA or return that modem and try a different one. 

 

[KingMoogle]

1 hour ago, Donut417 said:

Thats because on the modem those are not settings you need to worry about. The modem will connect what ever way the ISP needs to. Comcast issues both firmware and config file updates periodically, the ISP is actually the only ones that can issue any type of updates when it comes to cable modems. The LAG function is used if you needed to do more than 1 Gbps, some cable modems have like 4 ports. But you connect all of them to the same router and some how some way, you should get faster speeds, theoretically. However, most ISP's dont offer above 1 Gbps on coax yet. 

 

Thats strange. The only thing you should have to do is rebooting the modem after you connect a new device. Outside of that, nothing else needs to be done. What you might want to try is reseting the modem and connecting the router as that one device and see what happens. 

 

If none of that works, then you might want to RMA or return that modem and try a different one. 

 

Alright, so I just tried my older Arris modem.

I've used that modem successfully with 2 different xfinity accounts at two different locations (one including this one) and im getting the exact same results.

When I set this one up before I had zero issues with simply plugging it in and every single device on my network worked as soon as I plugged it in.

So now this is 3 different modems, 3 different models, 2 different makers. 

 

When I log into my xfinity account online it immediately says there is a problem with my internet and sends me to customer service.

So at this point I'm thinking it's definitly something on xfinities side and whenever I get someone with 3 years or less experience they never heard of it and tell me "well ive been doing this for 3 years and have never heard of it". No disrespect to the people I've spoken to from xfinity, but when you can't solve something it's usually best to send the customer through to a far more experienced member of the team as opposed to "best of luck". lol.

 

Thanks for trying Donut, if you hear anything definitely let me know!
I appreciate you taking the time to assist meh.

[kirashi]

6 minutes ago, KingMoogle said:

Alright, so I just tried my older Arris modem.

I've used that modem successfully with 2 different xfinity accounts at two different locations (one including this one) and im getting the exact same results.

When I set this one up before I had zero issues with simply plugging it in and every single device on my network worked as soon as I plugged it in.

So now this is 3 different modems, 3 different models, 2 different makers. 

Just to confirm, when you change the device plugged into the modem (your router, PC, game console, etc.) are you power cycling the modem?

 

Asking because most Cable ISPs CMTS chassis (Cable Modem Termination System, such as the ARRIS E6000) will only hand out an IP address to the MAC address of whatever the first device is that's plugged into the modem. If you physically change the device connected to the modem via ethernet without rebooting the modem, the CMTS may not acknowledge this change, and thus may not hand out an IP to the new device...

https://www.commscope.com/product-type/broadband-access-network-systems/cmts-ccap/ccap/e6000/?utm_source=arris&utm_medium=redirect

[Donut417]

1 minute ago, KingMoogle said:

but when you can't solve something it's usually best to send the customer through to a far more experienced member of the team as opposed to "best of luck". lol.

Not sure you know how CSR's work. Comcast expect them to sell you more services, even though the current services dont work. Comcast is known to have some of the shittiest customer service in the industry. 

 

https://www.dslreports.com

 

If you sign up for an account, you should see ISP Direct to members support section on the right side, just scroll down. Comcast has technical support forum on this site. Its staffed by the guys out of Philly, the Comcast HQ, not the local idiots you have been talking to. Ive heard they have been getting swamped with requests, but make a post. Explain to them what's going on. You might get more action from them. 

[KingMoogle]

2 minutes ago, Donut417 said:

Not sure you know how CSR's work. Comcast expect them to sell you more services, even though the current services dont work. Comcast is known to have some of the shittiest customer service in the industry. 

 

Hahahah oh I know. I've worked 4-5 years as an installation/repair tech and I&R/I&M for U-verse, Fairepointe communications, Alta, Linx, ah wait, Linx wouldn't count since they do mass cable pulling.

I guess mine and my teams way of doing things at AT&T was to actually escalate the situation as opposed to trying to sell "better" equipment.

 

However, when it comes to THIS situation the reason im so lost is because I've literally never had this problem before.

I've used the older surfboard straight out of the box with none of this happening, and I've used it at this house as well.
Apologies if i'm repeating myself.

[KingMoogle]

OKAY SOMETHING NEW! With my old modem, after about 20 or so minutes or so all of my other devices connected to my nighthawk S8000 switch just began working... 

Oddly I waited somewhere around 3 hours yesterday and nothing happened on the newer CM1000 modem, but the modem i have on now is like 5+ years old

SB6580.

I'm going to try the new model again and wait an hour to see if everything comes up like this just did.

[KingMoogle]

11 minutes ago, kirashi said:

Just to confirm, when you change the device plugged into the modem (your router, PC, game console, etc.) are you power cycling the modem?

 

Asking because most Cable ISPs CMTS chassis (Cable Modem Termination System, such as the ARRIS E6000) will only hand out an IP address to the MAC address of whatever the first device is that's plugged into the modem. If you physically change the device connected to the modem via ethernet without rebooting the modem, the CMTS may not acknowledge this change, and thus may not hand out an IP to the new device...

https://www.commscope.com/product-type/broadband-access-network-systems/cmts-ccap/ccap/e6000/?utm_source=arris&utm_medium=redirect

When I did a complete reset, I took the ethernet out of computer A that it was already working on and connected it to Computer B.

Computer B began working while computer A would no longer connect to the internet. 

 

So I tried resetting (removing the ethernet and coax cable, holding the reset for 20-30 seconds, reconnected the coaxial and let it go solid blue, connected the ethernet).

and connecting only to my router, but it still would not recieve a connection to the internet. 

[kirashi]

7 minutes ago, KingMoogle said:

When I did a complete reset, I took the ethernet out of computer A that it was already working on and connected it to Computer B.

Computer B began working while computer A would no longer connect to the internet. 

Uhhh yeah that normally happens when you remove the ethernet cable from a computer that only has wired networking...?

 

8 minutes ago, KingMoogle said:

So I tried resetting (removing the ethernet and coax cable, holding the reset for 20-30 seconds, reconnected the coaxial and let it go solid blue, connected the ethernet).

and connecting only to my router, but it still would not recieve a connection to the internet. 

 

 

Do you have another router you can test with so as to rule out problems with your existing router?

[BlackManINC]

11 minutes ago, KingMoogle said:

When I did a complete reset, I took the ethernet out of computer A that it was already working on and connected it to Computer B.

Computer B began working while computer A would no longer connect to the internet. 

 

So I tried resetting (removing the ethernet and coax cable, holding the reset for 20-30 seconds, reconnected the coaxial and let it go solid blue, connected the ethernet).

and connecting only to my router, but it still would not recieve a connection to the internet. 

RMA that shit dude......Because it sounds like there is a problem with the modem itself. Its either that, or something is wrong with the NIC card in computer B. Can you use the modems WIFI using your cell phone? Because if its not working, you'll notice it with the phone because it won't have an IP address assigned to it under the "about phone" section, "network", in the settings menu. I think this is one way you can rule out the modem. 

[KingMoogle]

1 hour ago, kirashi said:

Uhhh yeah that normally happens when you remove the ethernet cable from a computer that only has wired networking...?

 

 

I reconnected it afterwards to try it again after testing the second computer. I'm not saying I unplugged the ethernet cable and it wasn't working anymore, lol.

Even if I have the ethernet coming from the modem to an ethernet switch that I have connected to multiple devices, it will only give internet access to the device I used to activate the xfinity service.

What I was saying above is that I Tested it with CompA and CompB.

When I activated the service with CompA, I would then try to connect compB to ethernet and it would not get internet and visa versa even when both are hardwired into the modem at the same time through a switch.

 

1 hour ago, kirashi said:

Do you have another router you can test with so as to rule out problems with your existing router?

 The router itself will not recieve internet. I have 3 modems:
an xfinity supplied modem, Arris SB8200, and an Arris 6580 (older model only capable of 280down).

 

[kirashi]

3 minutes ago, KingMoogle said:

When I activated the service with CompA, I would then try to connect compB to ethernet and it would not get internet and visa versa even when both are hardwired into the modem at the same time through a switch.

 

Ah, my apologies, I missed that you were using a switch. An unmanaged network switch cannot assign IP addresses itself - it gets those from another device running a DHCP server, usually a router connected to the switch. If you've only got your modem -> network switch -> devices, and Comcast has only provisioned your modem for one IP address, then only one device will be able to pull a public IP address. You need a router to hand out internal local IP addresses, or more IPs from Comcast.

[KingMoogle]

2 hours ago, BlackManINC said:

RMA that shit dude......Because it sounds like there is a problem with the modem itself. Its either that, or something is wrong with the NIC card in computer B. Can you use the modems WIFI using your cell phone? Because if its not working, you'll notice it with the phone because it won't have an IP address assigned to it under the "about phone" section, "network", in the settings menu. I think this is one way you can rule out the modem. 

Thanks for the reply, but I know both CompA and CompB work perfectly on the internet.

CompB even has 2 different ethernet ports so I can always troubleshoot both if one seems like it's acting up.

But I've been comunicating with everyone here on CompB so far. 

 

So what has happend now, my old Arris 6580 brought everything online after 20-35 or so minutes and I got excited.

I thought maybe things are just finally working and I plugged my 8200 back in.

Now I'm getting a new error "Sorry, we can't find this device" so I called in and got a T1 tech, Supervisor, and an advanced network tech on the line and it's pretty much down to I have to take the modem to an xfinity store so they can scan it in and assign it to my account because after all the troubleshooting ive been doing for the past 8 hours straight, the xfinity system deleted the modem completely. 

 

I wish it were as simple as an RMA situation, lol. But this is the second modem in 2 days, different make and model even with the exact same problem. So I really think it's something up with their system taking forever to recognize and allow the modem 100% functionality. So we'll see o/

[KingMoogle]

1 minute ago, kirashi said:

Ah, my apologies, I missed that you were using a switch. An unmanaged network switch cannot assign IP addresses itself - it gets those from another device running a DHCP server, usually a router connected to the switch. If you've only got your modem -> network switch -> devices, and Comcast has only provisioned your modem for one IP address, then only one device will be able to pull a public IP address. You need a router to hand out internal local IP addresses, or more IPs from Comcast.

Oh it's alright, no offense was taken.

I have the Nighthawk S8000 Smart Managed Plus Gaming Switch.

I momentarily had internet on all of my devices through that while connected to my 5 year old 6580 router, but it's only D3.0 while my new 8200 is D3.1 and I do have a gigabit connection and the 3.0 only goes up to 280-300 down and 5 up.

 

Currently I'm using the xfinity modem until later today when I can go to the xfinity store, have them scan in my 8200 and get things going, hopefully, lol.