Networking

From Linux 101, The beginner's guide to all things Linux.

If you have read the devices article, you may have noticed that one particularly large topic is completely missing: networking.

Linux handles networking in a special manner -- there is no /dev entry for network devices.

Despite there being no /dev entries, Linux does still call network connections by special names:

• ethX for network connections (wired/wireless)
• pppX for modem connections
• wlanX for particular wireless cards (wavelan series)

where X is some number, starting from 0 and counting up.

Most computers now-a-days have at least eth0; that is, at least one network connection.

The one pitfall to networking support is that each distribution handles it differently. Some have nice GUI configuration tools, others just use start scripts.

Another pitfall to Linux and networking is that it will not automagically connect onto networks like Windows. Networks are inherently a security risk, so it will be up to the root user to tell the system when to connect to the network.

You can set up your startup scripts to attempt to connect to the network, but if it fails, it will not automatically attempt to connect to the network without you requesting it. A workaround tool is listed below, but Linux will not do this on its own.

[edit] Important tools

ifconfig 

is your InterFace configurator tool. If you use static addresses, want to change your hardware address, and the like, this is the tool you would use.

dhcpcd 

is your DHCP Client Daemon, which if you use DHCP to configure your IP address (like on the Clemson network) then you will likely use it.

ifplugd 

if you disconnect your wire conenction often, ifplugd is a daemon that will check for a wire connection every so often to automatically detect the network.

iwconfig 

will be used to configure your wireless card's encryption key, and more.