Here's a summary of this chapter's main points:

• An IP address is the number that uniquely identifies a machine across a network.
• The netcfg tool is used to configure basic network services such as setting up the network card or PPP connection, establishing routes, setting the hostname and DNS information, and setting up the /etc/hosts file.
• Should you need to hand-configure your network interface, use the ifconfig command to set up the IP number, netmask, and broadcast address.
• When configuring a network by hand, don't forget to set the routing table with the route command. Without it, your machine will not know where to send packets!
• The Domain Name System (DNS) is used for resolving hostnames across the Internet to their actual IP numbers. DNS servers are often called nameservers.
• When establishing a small network, it is a good idea to configure a caching nameserver to reduce load on your connection to other networks.
• The Network File System (NFS) is used to share disks from machine to machine. It is a very powerful tool enabling you to keep one copy of data and have all your machines on the network access it.
• If you share a disk with another host via NFS, you should have complete trust in the administrator of that host. NFS security relies on good deal of trust.
• The Network Information System (NIS) is used for sharing common files on the network. This is most often used for sharing user information (such as /etc/passwd,/etc/group).
• If you have several NIS clients, you should set up NIS slave servers and have them share the load.
• Use netgroups if you want to cluster users into manageable groups for access control.
• PPP is used to enable your machine to connect to an Internet Service Provider through a modem. Red Hat Linux has all the necessary support for doing this and is easily configured through the netcfg program.

After you have your machine configured and accessing the network, HAVE FUN WITH IT! You will quickly find uses for the network access that you could never even dream about on a standalone system. A word of warning, though—after you have put your machine onto a network, you will never want to take it offline.

Part IV

System Administration and Management

In This PART

• Getting Started with Red Hat Linux 299
• Essential System Administration 319
• Advanced System Administration 341
• GNU Project Utilities 351
• Backup and Restore 373