292Part IIIChoosing and Installing a Linux Distribution16.Choose a (Web site domain)
292Part IIIChoosing and Installing a Linux Distribution16.Choose a firewall configuration.The use of a firewall has significant impacton the security of your computer. If you are connected to the Internet or toanother public network, a firewall can limit the ways an intruder may breakinto your Linux system. Here are your choices: No firewall Select this security level if you are not connected to a public network and do not want to deny requests for services from anycomputer on your local network. Of course, you can still restrict accessto services by starting up only the services you want to offer and byusing configuration files to restrict access to individual services. Enable firewall Select this security level if you are connecting yourLinux system to the Internet for Web browsing and file downloading(FTP). By default, only services needed to enable Web browsing andbasic network setup, DNS replies, and DHCP (to serve addresses) areallowed at this level. If you enable the firewall and you know you want to enable access to particu- lar services, you can click the appropriate check boxes and allow incomingrequests for the following services: SSH (secure shell to allow remote login), Telnet (an insecure method of remote login), WWW (act as a Web server), Mail (act as a mail server), and/or FTP (act as an FTP server). You can alsoadd a comma-separated list of port numbers to the Other Ports box to openaccess to those ports, which effectively allows requests to services associ- ated with those port numbers. (The /etc/servicesfile lists which servicesare associated with which port numbers.) If you have a LAN that consists of trusted computers, you can click the box rep- resenting your interface to that LAN (probably eth0). Clicking the box allowsaccess to any services you care to share with the computers on your LAN. Click Next to continue. Adding firewall rules here results in rules being added to the /etc/sysconfig/ iptablesfile. The rules are run from the /etc/init.d/iptablesstartup scriptwhen you boot your system. 17.Choose language support.The default is your installation language. You caninstall support for additional languages by clicking the check boxes next tothe languages you want. Click the Select All button to install all supported languages to your system. When you are done, click Next to continue. 18.Choose a time zone.Select one from the list. To see a more specific view ofyour location, click World and choose your continent. From the UTC Offsettab, you can choose a time zone according to the number of hours away fromGreenwich Mean Time (GMT), known as the UTC offset. 19.Set root password. The root password provides complete control of yourFedora Linux system. Without it, and before you add other users, you willhave no access to your own system. Enter the password, and then type itagain in the Confirm box. (Remember the root user s password and keep itconfidential! Don t lose it!) Click Next to continue. Tip15_