Post-installation configuration

Network services

Рис. 6.4. Network services menu

The next step is to configure your networking equipment. Figure 6-4 shows the Network Services Menu. There are a number of ways to get to this menu:

• If you're running the recommended Custom installation, you'll get it automatically after the end of the installation.
• If you're running the Standard and Express installations, you don't get it at all: after setting up your network interfaces, sysinstall presents you with individual items from the Network Services Menu instead.
• If you're setting up after rebooting, or if you missed it during installation, select Configure from the main menu and then Networking.

The first step should always be to set up the network interfaces, so this is where you find yourself if you are performing a Standard or Express installation.

Setting up network interface

Figure 6-5 shows the network setup menu. On a standard 80x25 display it requires scrolling to see the entire menu. If you installed via FTP or NFS, you will already have set up your network interfaces, and sysinstall won't ask the questions again. The only real network board on this list is xl0, the Ethernet board. The others are standard hardware that can also be used as network interfaces. Don't try to set up PPP here; there's more to PPP configuration than sysinstall can handle. We'll look at PPP configuration in "Configuring PPP" .

Рис. 6.5. Network setup menu

In our case, we choose the Ethernet board. The next menu asks us to set the internet parameters. Figure 6-6 shows the network configuration menu after filling in the values. Specify the fully qualified local host name; when you tab to the Domain: field, the domain is filled in automatically. The names and addresses correspond to the example network that we look at in "Networks and the Internet" , on page 294. We have chosen to call this machine presto, and the domain is example.org. In other words, the full name of the machine is presto.example.org. It's IP address is 223.147.37.2. In his configuration, all access to the outside world goes via gw.example.org, which has the IP address 223.147.37.5. The name server is located on the same host, presto.example.org. The name server isn't running when this information is needed, so we specify all addresses in numeric form.

What happens if you don't have a domain name? If you're connecting to the global Internet, you should go out and get one—see page 318. But in the meantime, don't fake it. Just leave the fields empty. If you're not connecting to the Internet, of course, it doesn't make much difference what name you choose.

Рис. 6.6. Network configuration menu

As is usual for a class C network, the net mask is 255.255.255.0. You don't need to fill in this information—if you leave this field without filling it in, sysinstall inserts it for you. Normally, as in this case, you wouldn't need any additional options to ifconfig.

Other network options

It's up to you to decide what other network options you would like to use. None of the following are essential, and none need to be done right now, but you may possibly find some of the following interesting:

• inetd allows connections to your system from outside. We'll look at it in more detail on page 448. Although it's very useful, it's also a security risk if it's configured incorrectly. If you don't want to accept any connections from outside, you can disable inetd and significantly reduce possible security exposures.
• NFS client. If you want to mount NFS file systems located on other machines, select this box. An X appears in the box, but nothing further happens. See Chapters 24 and 25 for further details of NFS.
• NFS server. If you want to allow other systems to mount file systems located on this machine, select this box. You get a prompt asking you to create the file /etc/exports, which describes the conditions under which other systems can mount the file systems on this machine. You must enter the editor, but there is no need to change anything at this point. We'll look at /etc/exports in more detail on page 463.
• ntpdate and ntpd are programs that automatically set the system time from time servers located on the Internet. See page 156 for more details. If you wish, you can select the server at this point.
• rwhod broadcasts information about the status of the systems on the network. You can use the ruptime program to find the uptime of all systems running rwhod, and rwho to find who is running on these systems. On a normal-sized display, you need to scroll the menu down to find this option.
• You don't need to select sshd: it's already selected for you. See page 453 for further details of ssh and sshd.

You don't need to specify any of the remaining configuration options during configuration. See the online handbook for further details.