In this chapter we discuss Networking--how to configure a connection, using TCP/IP, SLIP, PPP or UUCP, and electronic mail and news.
Linux supports a full implementation of the TCP/IP (Transport Control Protocol/Internet Protocol) networking protocols. TCP/IP has become the most successful mechanism for networking computers worldwide. With Linux and an Ethernet card, you can network your machine to a local area network, or (with the proper network connections) to the Internet--the worldwide TCP/IP network.
Hooking up a small LAN of UNIX machines is easy. It simply requires an Ethernet controller in each machine and the appropriate Ethernet cables and other hardware. Or, if your business or university provides access to the Internet, you can easily add your Linux machine to this network.
The current implementation of TCP/IP and related protocols for Linux is called ``NET-3,'' and before that, ``NET-2.'' This has no relationship to the so-called NET-2 release of BSD UNIX; instead, ``NET-3'' in this context means the second implementation of TCP/IP for Linux.
Linux NET-3 also supports SLIP--Serial Line Internet Protocol and PPP--Point-to-Point Protocol. SLIP and PPP allow you to have dialup Internet access using a modem. If your business or university provides SLIP or PPP access, you can dial in to the SLIP or PPP server and put your machine on the Internet over the phone line. Alternately, if your Linux machine also has Ethernet access to the Internet, you can set up your Linux box as a SLIP or PPP server.
For complete information on setting up TCP/IP under Linux, we encourage you to read the Linux NET-3 HOWTO, available via anonymous FTP from sunsite.unc.edu. The NET-3 HOWTO is a complete guide to configuring TCP/IP, including Ethernet and SLIP or PPP connections, under Linux. The Linux Ethernet HOWTO is a related document that describes configuration of various Ethernet card drivers for Linux. The Linux Network Administrator's Guide, from the Linux Documentation Project, is also available. See Appendix A for more information on these documents.
Also of interest is the book TCP/IP Network Administration, by Craig Hunt. It contains complete information on using and configuring TCP/IP on UNIX systems.
You can use Linux TCP/IP without any networking hardware at all--configuring ``loopback'' mode allows you to talk to yourself. This is necessary for some applications and games which use the ``loopback'' network device.
However, if you want to use Linux with an Ethernet TCP/IP network, you need an Ethernet card. Common cards suchNK REL=d that /usr/X11R6/bin/X is a symbolic link to it.
If all else fails, try to start X ``bare''; that is, with a command
like:
You can then kill the X server (using
Ctrl-Alt-Backspace) and examine the
contents of /tmp/x.out. The X server reports any warnings or
errors--for example, if your video card doesn't have a dot clock
corresponding to a mode supported by your monitor.
The file VideoModes.doc, which is included in the XFree86 distribution, contains many hints for adjusting the values in your XF86Config file.
Remember that you can use Ctrl-Alt-Numeric + and Ctrl-Alt-Numeric - to switch between the video modes listed on the Modes line of the Screen section of XF86Config. If the highest resolution mode doesn't look right, try switching to a lower resolution. This lets you know, at least, that those parts of your X configuration are working correctly.
Also, adjust the vertical and horizontal size/hold knobs on your monitor. In many cases, it is necessary to adjust these when starting up X. For example, if the display seems to be shifted slightly to one side, you can usually correct this using the monitor controls.
Again, the USENET newsgroup comp.windows.x.i386unix is devoted to discussions about XFree86. It might be a good idea to read the newsgroups for postings related to video configuration. You might run across someone with the same problem.
There are also sample XF86Config files which have been contributed by users. Some of these are available on the sunsite.unc.edu archive in the /pub/Linux/X11 directory, and elsewhere. You might find a configuration file that somebody has already written for your hardware.