Connecting to the Internet

Introduction

Here we have something lots of users face up to in their early stages of setting Linux up: Connecting to the Internet.

Steps

We'll see how we can do it, step by step, and in an easy way:

1.) The first thing: check whether your kernel supports the PPP protocol or not; it's the protocol most often used by Internet providers.  Check by typing the following:

           dmesg | more
           

Scroll pages by pressing the space key.

You should see a line such as the following:

           PPP: version 2.2.0 (dynamic channel allocation)
           TCP compression code copyright 1989 Regents of the
           University of California
           PPP Dynamic channel allocation code copyright
           1995 Caldera, Inc.
           PPP line discipline registered
           

If you don't have it, don't worry, you'll simply have to recompile the kernel, selecting the appropiate options. How do you recompile the kernel? Well, this issue could well take a whole new article, but you can check it out in the SLUG Linux list or in any other you might be in. It is also well described in the README file distributed with the kernel source code.

2.) Next, go to the /etc/ppp directory, where we'll edit several files. 

The first one of them will be the so-called "options" file. 
Edit it with your favorite editor (not a few in Linux, indeed... ;-) and delete everything it may have, surely the word "lock".
Then write the following: 

           connect /etc/ppp/connect_file_name 
           crtscts  
           modem  
           passive  
           +ua /etc/ppp/ppp_provider_name 
          (only in case you are using Infovia in Spain) noipdefault 
           defaultroute  
           asyncmap a0000  
           lock  
           lcp-echo-interval 15   
           lcp-echo-failure 5  
           mtu 1500  
           /dev/modem 
           38400
           

Now, edit the file you wrote in the line connect in the "options" file. In my case, for example, I'll call it "dracnet": 

           chat -v ""  ATE0DTXXXXXXX CONNECT "" login: my_login  password: my_password
           

           Next, save the file. 
           

Where it reads ATE0DT, you can simply write ATDT. I write the E0 option in order to disable modem echo.
The XXXXXXX refers to your Internet provider telephone number; in case you are using Infovia (Spain), it will be 055. 

3.) Now edit the file associated with the line "+ua", in the options file, which in my case I'll call "dracnetppp": 

           my_login my_password
           

4.) Next, go back in the directory tree and position yourselves in the /etc directory, with cd ..

Once there, edit the file "resolv.conf". If you don't have it, no problem. Just write the following (always deleting anything it may contain before; assuming you're not networked with other computers, you can do it peacefully ;-): 

           domain provider.com  nameserver XXX.XXX.XXX.XXX
           

Note that the "domain" section is just the domain your provider uses. In my case it would be "dracnet.es". 

In the "nameserver" section you'll put the IP address of your provider's main name server. 
If you don't have these data available, please ask your provider for them, he or she will give them to you. 

5.) Now  go to /usr/bin (cd /usr/bin), and edit a file called connect, by writing the following: 

           pppd;tail -f /var/log/messages
           

Et voila!! Here we have our Linux box, ready to connect to the Internet. Just execute (from wherever we want) the file "connect", that's all.

When you execute it, you'll see, step by step, the connection process with our provider, thanks to the "tail" command we wrote in the "connect" script. When our IP address has been assigned, we can get out of "tail" by pressing Ctrl-C.