Question 2 Ethernet Ports Not Working Together Anymore

extraproblems

Distinguished
May 18, 2014
50
1
18,545
1
I hope someone can help me. I have an Arris SB8200 modem with 2 ethernet ports. I have been working from home for about 2 years now and I have never had an issue with plugging my home ethernet cord and my work ethernet cord in and have internet on both. Now all of the sudden I can only do one at a time. I have tried both cords, both ports and only can connect to one or the other when I reset the modem, even though both ports are lit up and recognized. Can anyone explain to me what has happened? Again, both ports and cords work, but only 1 at a time.
 

Ralston18

Titan
Moderator
This modem?

https://approvedmodems.com/cable-modems/arris-surfboard-sb8200/

From the link:

"On a cable modem, it’s unusual to come across two Ethernet connections. To allow two gadgets to be linked at the same time (the ISP must provide an extra IP address for this device – ISPs do not give additional IP addresses for home users), Arris included them. However, there are other purposes possible, such as link aggregation or establishing a failover system. "

Not sure what may have transpired before in order for both ports to be working. However, maybe events and circumstances have caught up a bit and/or a modem reset undid something previously in place.

Have you called your ISP?

= = = =

Do you happen to have a home router? If so, make and model? How is the router connected into the network?

= = = =

On both your home Ethernet computer and on your work Ethernet computer run "ipconfig /all" (without quotes) via the Command Prompt.

Post the results from each computer be sure to identify results by computer.

The results may provide some clue as to what is/has happened.
 
That is how I would expect it to work. What is more surprising is that you where ever able to plug 2 devices in and get them to function.

This is a modem and not a modem/router. Your ISP will generally only give you 1 IP address so only 1 device can be active. That is why people have routers to share the single IP.

Having 2 ethernet ports on that box is so they can pretend it can go faster than 1gbit. The fine print though says you need a second IP address. You might be able to port bond the ports to a router that also supports it port bond does a extremely poor job of load balancing.
 

extraproblems

Distinguished
May 18, 2014
50
1
18,545
1
don't use a router but may have to get one. I'm on mobile since I'm on work pc. I will have to call ISP later on. but I'm assuming they will play dumb and say I should not have been able to use both in the first place.

this actually happened before last year but it magically started working again after a day. I did have a power outage the other day, not sure if that affected the modem. I have unplugged, used reset button, restarted both pcs, but only 1 will work at a time.
 

ASK THE COMMUNITY