4 Dhcp - Novell LINUX ENTERPRISE SERVER 10 SP2 - INSTALLATION AND ADMINISTRATION Installation Manual

DHCP
The purpose of the dynamic host configuration protocol (DHCP) is to assign network
settings centrally from a server rather than configuring them locally on each and every
workstation. A host configured to use DHCP does not have control over its own static
address. It is enabled to configure itself completely and automatically according to di-
rections from the server. If you use the NetworkManager on the client side, you do not
need to configure the client at all. This is useful if you have changing environments
and only one interface active at a time. Never use NetworkManager on a machine that
runs a DHCP server.
TIP: IBM System z: DHCP Support
On IBM System z platforms, DHCP only works on interfaces using the OSA and
OSA Express network cards. These cards are the only ones with a MAC, which
is required for the DHCP autoconfiguration features.
One way to configure a DHCP server is to identify each client using the hardware address
of its network card (which should be fixed in most cases), then supply that client with
identical settings each time it connects to the server. DHCP can also be configured to
assign addresses to each interested client dynamically from an address pool set up for
that purpose. In the latter case, the DHCP server tries to assign the same address to the
client each time it receives a request, even over longer periods. This works only if the
network does not have more clients than addresses.
DHCP makes life easier for system administrators. Any changes, even bigger ones, re-
lated to addresses and the network configuration in general can be implemented centrally
by editing the server's configuration file. This is much more convenient than reconfig-
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