9.1. Gateway Configuration

One way to access the Internet is to connect through a modem or a dedicated phone line. Section 3.7 touched briefly on using the KPPP graphical utility to configure both types of Internet connections. I will not develop this subject, because there is nothing to add here in terms of the security. You can easily find numerous documents on the Internet describing how to configure Internet connections using KPPP. I will only make a few remarks in this respect.

If you use the graphical connection-configuration utility, you should know that all scripts are stored in the /etc/ppp and /etc/sysconfig/network-scripts directories. Make sure that you familiarize yourself with the files contained in these directories.

After connecting to the Internet, ascertain that a DNS server (which maps symbolic Internet site names to their corresponding IP addresses) is available. This can be done by pinging some Web site, like this:

 ping www.redhat.com

If there is a response, a DNS server is available; otherwise , you will only be able to address Web pages by using their IP addresses. If the DNS server is not available, you can specify its address manually. You will have to obtain the DNS server address from your Internet provider and add it to the /etc/resolv.conf file as follows :

 nameserver 191.168.1.1

Instead of the 191.168.1.1 value, specify the address given to you by the provider. If the provider gives you more than one address, all of them can be added to the file as follows:

 nameserver 191.168.1.1 nameserver 191.168.1.2