I had an SB 6141 modem with my TP-link C9 router. The modem died. I bought another SB 6141. My router did not die so I am still using it.

I plugged in and activated the new SB 6141 modem and tested it with my 2 desktops (Windows 7 and Kubuntu some version #). Both worked just as they did when I had my older SB 6141 modem.

I tried getting wired connectivity with my laptop (Mint 18.1). There was no activity when using both the new modem and same router. There was no connectivity when using only the new modem.

Please note this laptop worked perfectly well with my old SB 6141 modem. Now that I have a new SB 6141 modem (yes, same model and make) I can't get internet connectivity on the laptop. No, it doesn't matter if I use my router in the process. Yes, my other 2 computers (Windows & Kubuntu) work well with the new SB 6141 modem and old TP-link C9 router.

In other words, just my linux laptop is not getting internet connectivity even though I am using the exact same model and make modem. The ONLY thing that has changed is that I got a new SB 6141 modem to replace the one that died.

I don't care about wireless connectivity for the laptop. I only want wired connectivity.

What should I do?

Thank you!

When you connect do you at least get a link light?

You can also check the laptop's link status with ethtool eg

If that checks out, see if you're getting an IP address
and

I don't use cable internet in aussieland but a few suggestions based on this site
https://wikidevi.com/wiki/Motorola_SURFboard_SB6141

it does not have a power button. so apparently to reset it you toggle off at the wall?

show us the output to this command pls

the most recent success line will be the first line and for me its
dhcp6 (eno1): state changed timeout -> done


also show us the output to this command
I am a slow typer so edit just saw ferrari posts

If you haven't already go ahead and shutdown/reboot the laptop and router just because it is the Windows thing to do. Does the laptop show a LAN connection in the NetworkManager applet?

Typically with most home broadband cable service you only get one dynamic IP address which is based upon the MAC address of the connected device. If you plug the laptop directly into the MODEM you have to reset power.

In general I can't think of anything that would of caused the problem. It might be that the laptop tried to check for updates while you were switching to the the MODEM and caused some sort of network disconnect.

ferrari - Yes, I get all the lights. I will try your suggestions tomorrow as I am away tonight.

aus9 - Yes I must unplug the power to power cycle it. There is no on / off switch.

michaelk - Yes, in my laptop there is a little icon in the lower right corner that shows no connection whether I plug the modem directly into the laptop or route it through the router then laptop.

What is really odd is this: With my old modem, I could have all 3 plugged in (wired connection) at the same time with no problems. I could literally pull an ethernet cable out of one of my computers or plug one in, without any problems.

The ONLY thing that changed was replacing the dead SB 6141 with a new SB 6141.

did you set up any MAC filtering?

I don't even know what that is. LOL.

Replacing the MODEM should not affect the LAN side of the router.

Is the laptop configured with a static IP address or use DHCP?

deleted - didn't read closely enough.

michaelk -

Sorry I really don't know but I could check later today when I arrive home.

How would I check?

I only use wired connection with the laptop. I don't use wireless with it.

I do know that I haven't changed any laptop settings.

Look at the settings via network manager applet.

Regarding the "static" or "DHCP" question, I see the following tabs:

A) General - The following are checked: 1) Auto connect to this network when it is available, 2) All users may connect to this network

B) Ethernet - The followning fields are shown: 1) "Device" with a strange combination of digits (not my MAC number), 2) "Cloned MAC Address" which is blank, 3) "MTU" which states "automatic"

C) 802.1x Security - This has an unchecked box stating "use 802.1x security for this connection"

D) DCB - This has an unchecked box stating "use data center bridge for this connection"

E) IPv4 Settings - This has a field labelled "Method" which states "Automatic "(DHCP)"

F) IPv6 Settings - This has a field labelled "Method" which states "Automatic"

I looked at my router settings under "Internet" and it states "Dynamic".

Does any of this information help?

ferrari & aus9 -

Regarding your earlier posts:

Here is a copy & paste from my terminal output (I bolded the input to make things easier to see). This output was obtained while my modem was on, my router was on, my Windows 7 desktop was on and obviously connected via router, and my laptop was on but not connected even though I had an ethernet cable in it.

I do have a firewall on both Windows 7 (whatever it comes with) and Mint (whatever it comes with) but neither has ever posed a problem.

catadmin@CATLAP ~ $ /sbin/ethtool eth0
Settings for eth0:
Cannot get device settings: No such device
Cannot get wake-on-lan settings: No such device
Cannot get message level: No such device
Cannot get link status: No such device
No data available
catadmin@CATLAP ~ $ sudo /sbin/ethtool eth0
[sudo] password for catadmin:
Settings for eth0:
Cannot get device settings: No such device
Cannot get wake-on-lan settings: No such device
Cannot get message level: No such device
Cannot get link status: No such device
No data available
catadmin@CATLAP ~ $ ip address
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: enp3s0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast state DOWN group default qlen 1000
link/ether f4:30:b9:39:0a:d7 brd ff:ff:ff:ff:ff:ff
3: wlo1: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000
link/ether d8:0f:99:0b:3b:5f brd ff:ff:ff:ff:ff:ff
catadmin@CATLAP ~ $ ip route
catadmin@CATLAP ~ $ journalctl -r | grep dhcp
Jul 25 16:32:06 CATLAP NetworkManager[940]: <info> [1501018326.2982] dhcp6 (enp3s0): state changed bound -> done
Jul 25 16:32:06 CATLAP NetworkManager[940]: <info> [1501018326.2982] dhcp6 (enp3s0): canceled DHCP transaction, DHCP client pid 2382
Jul 25 16:32:06 CATLAP NetworkManager[940]: <info> [1501018326.2966] dhcp4 (enp3s0): state changed bound -> done
Jul 25 16:32:06 CATLAP NetworkManager[940]: <info> [1501018326.2965] dhcp4 (enp3s0): canceled DHCP transaction, DHCP client pid 2088
Jul 25 16:29:15 CATLAP nm-dispatcher[2087]: req:3 'dhcp6-change' [enp3s0]: start running ordered scripts...
Jul 25 16:29:15 CATLAP nm-dispatcher[2087]: req:3 'dhcp6-change' [enp3s0]: new request (1 scripts)
Jul 25 16:29:15 CATLAP NetworkManager[940]: <info> [1501018155.9744] dhcp6 (enp3s0): state changed unknown -> bound, event ID="b9:39:0a:d7|1501018155"
Jul 25 16:29:15 CATLAP NetworkManager[940]: <info> [1501018155.1229] dhcp6 (enp3s0): dhclient started with pid 2382
Jul 25 16:29:15 CATLAP NetworkManager[940]: <info> [1501018155.1190] dhcp6 (enp3s0): activation: beginning transaction (timeout in 45 seconds)
Jul 25 16:29:14 CATLAP NetworkManager[940]: <info> [1501018154.0546] dhcp4 (enp3s0): state changed unknown -> bound
Jul 25 16:29:13 CATLAP NetworkManager[940]: <info> [1501018153.8502] dhcp4 (enp3s0): dhclient started with pid 2088
Jul 25 16:29:13 CATLAP NetworkManager[940]: <info> [1501018153.8478] dhcp4 (enp3s0): activation: beginning transaction (timeout in 45 seconds)
Jul 25 16:29:13 CATLAP NetworkManager[940]: <info> [1501018153.6209] dhcp4 (enp3s0): state changed expire -> done
Jul 25 16:29:13 CATLAP NetworkManager[940]: <info> [1501018153.6208] dhcp4 (enp3s0): canceled DHCP transaction, DHCP client pid 1899
Jul 25 16:29:13 CATLAP NetworkManager[940]: <info> [1501018153.6041] dhcp4 (enp3s0): state changed bound -> expire
Jul 25 16:28:52 CATLAP nm-dispatcher[2062]: req:1 'dhcp4-change' [enp3s0]: start running ordered scripts...
Jul 25 16:28:52 CATLAP nm-dispatcher[2062]: req:1 'dhcp4-change' [enp3s0]: new request (1 scripts)
Jul 25 16:28:52 CATLAP NetworkManager[940]: <info> [1501018132.2016] dhcp4 (enp3s0): state changed bound -> bound
Jul 25 16:28:40 CATLAP nm-dispatcher[2017]: req:1 'dhcp4-change' [enp3s0]: start running ordered scripts...
Jul 25 16:28:40 CATLAP nm-dispatcher[2017]: req:1 'dhcp4-change' [enp3s0]: new request (1 scripts)
Jul 25 16:28:40 CATLAP NetworkManager[940]: <info> [1501018120.8296] dhcp4 (enp3s0): state changed bound -> bound
Jul 25 16:28:29 CATLAP nm-dispatcher[1082]: req:3 'dhcp4-change' [enp3s0]: start running ordered scripts...
Jul 25 16:28:29 CATLAP nm-dispatcher[1082]: req:3 'dhcp4-change' [enp3s0]: new request (1 scripts)
Jul 25 16:28:29 CATLAP NetworkManager[940]: <info> [1501018109.8245] dhcp4 (enp3s0): state changed unknown -> bound
Jul 25 16:28:29 CATLAP NetworkManager[940]: <info> [1501018109.7604] dhcp4 (enp3s0): dhclient started with pid 1899
Jul 25 16:28:29 CATLAP NetworkManager[940]: <info> [1501018109.7551] dhcp4 (enp3s0): activation: beginning transaction (timeout in 45 seconds)
Jul 25 16:28:29 CATLAP NetworkManager[940]: <info> [1501018109.7539] dhcp4 (enp3s0): state changed bound -> done
Jul 25 16:28:29 CATLAP NetworkManager[940]: <info> [1501018109.7539] dhcp4 (enp3s0): canceled DHCP transaction, DHCP client pid 1323
Jul 25 16:28:25 CATLAP NetworkManager[940]: <info> [1501018105.1041] dhcp4 (enp3s0): state changed unknown -> bound
Jul 25 16:28:23 CATLAP NetworkManager[940]: <info> [1501018103.1301] dhcp4 (enp3s0): dhclient started with pid 1323
Jul 25 16:28:23 CATLAP NetworkManager[940]: <info> [1501018103.1242] dhcp4 (enp3s0): activation: beginning transaction (timeout in 45 seconds)
catadmin@CATLAP ~ $ sudo ifconfig
enp3s0 Link encap:Ethernet HWaddr f4:30:b9:39:0a:d7
UP BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:14382 errors:0 dropped:0 overruns:0 frame:0
TX packets:3299 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:4690196 (4.6 MB) TX bytes:450973 (450.9 KB)

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:65536 Metric:1
RX packets:2551 errors:0 dropped:0 overruns:0 frame:0
TX packets:2551 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1
RX bytes:182847 (182.8 KB) TX bytes:182847 (182.8 KB)

catadmin@CATLAP ~ $

I should add:

1) I again tried plugging the modem directly into the laptop. After power cycling, the laptop did have internet connection. Thus, I can rule out a problem with the modem and laptop. Thus the problem must be with routing.

2) I tested the ethernet cables and they worked elsewhere, so I am sure the ethernet cables are fine.