1. Issue-3 Internet Working

Greetings, this is Issue-3-Internet-Working, all about getting networking up and running.

The best reference texts are the NAG (network administrators guide), and the NET-3 HOWTO in the LDP printed compendium, and on-line.

1.1 Drop-in and change the values - example configuration
1.2 modem + ethernet card
1.3 SLIP or PPP
1.4 dial_ppp
1.5 Apps
1.6 sendmail


Drop-in and change the values - example configuration

You may find Raven easier than some docs, and save some time, because it uses "realistic example values", rather than generic foo/bar descriptions. However, you must remember to change the values to yours! Obvious really.

Do refer back to the main LDP docs, as they cover more variations, of different situations, However, once you have a working system, they will make more sense.

You should also use your imagination, and think up a different number than 67, and a different set of host names. Allocating IP_addresses is discussed in Issue-5-Planning, basically is my TCP/IP address on my private ethernet LAN.

Also your distribution may be configured differently than mine, so refer to the excellent docs that came on your CDROM's and installation programs.


modem + ethernet card

The configuration files used here, work for a machine with a modem and an ethernet card, ie a typical office/home machine. I recommend that you get an ethernet card anyway, because it allows you to take the machine anywhere (or bring a friends machine in), and connect over ethernet, with only a few edits to /etc/hosts and /etc/rc.d/rc.inet1 (whatever).

If you don't have an ethernet card, this configuration will still work, as long as the loopback interface works correctly. To link two machines without ethernet, you can use a null modem serial cable and PPP or SLIP. You can also use a PLIP parallel cable, and the PLIP driver.

You shouldn't need the dummy interface, but it may help to 'hold' the IP_ADDR for apps that need it, when the PPP link is down.



Both are documented. Most people are moving towards PPP, but SLIP is still a common option, for connecting to your Internet Service Provider.

You will have to modify the chat script, or dip script, so that you phone the correct telephone number, and login as the correct name using your secret password.

In addition, different ISP's have different greeting messages, which is how the scripts know they are properly connected, and my ISP asks me if I want SLIP or PPP.

After connecting, you may have additional parameters that need setting, your ISP will help you. These work for me.



Raven is a shareware magazine, but dial_ppp is available elsewhere as a Free package. It shows the files that you have to install to configure PPP (as well as the PPP package itself).

dial_ppp was started as an article in Raven, that enables a non-root user (me) to get root permissions to establish and break the PPP connection, in a "safe and controlled manner", and to do so from the X11 desktop, without having to switch console, or su.

Someone did make a big show of telling me on usenet that sudo was a pre-existing wheel, so why did I bother? Good question see sudo(8)



As well as making the connection you want to locate and configure apps to run over it. There are many choices, you want an email reader, a news reader, web browser and an ftp client.

With a local LAN, or even over a dial-up connection you can become a web server, by installing Apache or another httpd (daemon).



Configuring sendmail is not difficult, but it can be confusing, when you want something now. Raven has a 10 line configuration that works for a typical home machine, background information about how to test it and how it works.



They've changed Linux again!

Now the 2.1 kernel requires netmask to be specified in /etc/rc.inet1, on the route command. Sad but true.

No they've removed it! It's harmless to have the command option and SVR4 users should know that they do need it.