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I currently only have wired internet via a cable modem connected to an Airlink 101 ASW105 switch. It works fine for my wife's mac. However, my laptop does not connect; I've tried connecting via eth0 and tried creating a new wired connection- but both fail to connect.

It's not a hardware problem with my cables or the network hardware, as my wife's machine has been used to test all cables and ports etc, other than that of my laptop.

So, how can I go about connecting to this network via commands on the terminal?

If you need more information please fire away.

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You forgot to describe the problem. You just say it "does not connect", but don't explain how you tried to connect it or what happened when you tried. –  David Schwartz Sep 19 '13 at 19:21

2 Answers 2

If you're in the US, you may need to have a router between the switch and the cable modem that can do nat and dhcp. Most routers nowadays have builtin switches, so it may obviate the use of your switch.

To confirm this, try powering off the wife's mac, then powering on your laptop, if you get an ip address and surf the web, then power on the wife's mac. I'd expect that her mac won't be able to surf if you are (and vice versa). This indicates that the cable modem is only handing out 1 ip address, which means that you'll need a router connected to the cable modem to handle nat.

Good Luck!

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If your wife's pc connects to the outisde world, then you certainly already have a NAT DHCP server. From now on, I will assume you are under Linux, since you call the Ethernet IF eth0.

If you wish to diagnose your problems, you may try a manual connection via these commands:

sudo service network-manager stop
sudo ifconfig eth0 up
sudo dhclient -v eth0

At this point, you should start seeing dhcp offers rolling in.

Normally ethernet connections are quite sturdy, and they do not require tweaking of parameters to work. But if you get no DHCP offers, such tweaking is called for. In this case, you should identify your ethernet card by means of the following command:

lspci | grep Ethernet

which will tell vendor and model (make sure you write down the all-important code inside the square parentheses, [xxxx:yyyy]. Now check if you have a proper driver for this card:

sudo lshw -C network

(if you do not have the program lshw, install it by means of: sudo apt-get install lshw, or sudo pacman -S lshw, or sudo yum lshw...). If it says UNCLAIMED in the Ethernet part of the output (careful, there will be a part on your wifi connection), it means your pc does not have a suitable driver for your ethernet card. This can happen because your card is too new, too old, or requires some kind of proprietary software which your distro feels you have to ask for explicitly. If it does not say UNCLAIMED, check your driver's name.

Now you may search Google with your distro name, your card code [....], your driver's name, and the keyword PROBLEM.

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