Linux System Administration

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Chapter 8: Local Network Services

machines or even individual machines. Here’s an example of a global configuration

section at the top of a dhcpd.conf file:

option domain name "host2.centralsoft.org";

Providing Static IP Addresses

Workstations usually function fine with dynamic addresses (that is, addresses that

can change periodically or upon reboot), but servers usually benefit from static

addresses so that their addresses don’t change while they’re in the middle of a ses-

sion with a client. Thus, DHCP lets you specify static IP addresses for particular sys-

tems in dhcpd.conf. Let’s do this in steps.

First, set up the subnet, broadcast address, and routers:

subnet 192.168.1.0 netmask 255.255.255.0

option broadcast-address 192.168.1.255;

option routers 192.168.1.1;

Next, add a host section for each machine on your network. To do this, you need to

know the hardware address (often called the MAC address) for each network card,

which you can determine by using the ifconfig command on the host. Here’s an

example

host section:

# ethernet MAC address as follows (Host's name is "laser-printer"):

host laser-printer {

hardware ethernet 08:00:2b:4c:59:23;

fixed-address 192.168.1.10;

}

host1.centralsoft.com {

hardware ethernet 01:0:cO:2d:8c:33;

fixed-address 192.168.1.5;

}

Create a configuration clause like this for each server needing a static lP address, and

add it to the configuration file.

Assigning IPv6 ...