Installing and Administering Internet Services

Chapter 6 273
Dynamic Host Configuration Protocol (DHCP)
Configuring DHCP
Enabling DHCP on a System Not Initially Configured
with DHCP
1. As root, start SAM.
2. Double-click Networking and Communications.
3. Double-click Network Interface Cards.
4. Highlight the card you wish to enable DHCP on.
5. Go to the Actions menu and select Configure.
6. Click once on the Enable DHCP button.
7. Click OK and exit SAM.
Your system will start using DHCP after the next reboot.
bootptab and dhcptab Files
Two configuration files, bootptab and dhcptab, are used for your DHCP
configuration. These files contain DHCPtab pool and device group
information, as well as the start and end addresses or bootptab has fixed
address devices.
Configuration changes made using SAM are written to these files. You
can also manually edit these files if desired, although most of your work
will probably be performed using SAM. However, it is recommended that
you use SAM to configure DHCP.
The bootptab file contains configuration information for old BOOTP
clients as well as DHCP clients with fixed IP addresses. The bootptab
file also contains configuration for relay agents.
The dhcptab file contains configuration information for DHCP pool or
device groups, where clients are assigned IP addresses from a pool of
currently unused addresses.
For details on how to edit the configuration files manually, see the
dhcptools manpages.
Converting BOOTP Clients to DHCP Clients
Because DHCP makes allocating IP addresses easier, you may want to
convert old BOOTP clients to DHCP clients. You can do this by using the
allow-bootp-clients option of the bootpd(1M) command. You can
refer to this man page for detailed information. You can make an old