Installing and Administering Internet Services

254 Chapter6

Dynamic Host Conﬁguration Protocol (DHCP)

DHCP Components and Concepts

The primary components of DHCP discussed in this section include the

DHCP server, DHCP client, and DHCP leases.

DHCP Servers

The DHCP server dispenses and manages network IP addresses. It

assigns IP addresses to clients that are connecting to the network for the

ﬁrst time. When a client connects to the network, the server

automatically assigns it an IP address from an appropriate pool of

addresses.

You can have multiple DHCP servers on your network as long as their

subnet pools do not overlap. However, it is recommended that you have

only one DHCP server for your entire network. The server is responsible

for a pool of IP addresses. It can give out an IP address to a client

requesting a new conﬁguration from the pool of IP addresses for which it

is responsible. When a client asks for conﬁrmation of its existing

conﬁguration, the server conﬁrms the conﬁguration.

DHCP is a superset of the older BOOTP bootstrap protocol. The HP-UX

DHCP server will service older BOOTP clients. And DHCP servers and

clients from different vendors interoperate very well with one another.

DHCP Clients

DHCP server supplies DHCP clients with sufﬁcient information to

establish an endpoint for network communications. It also supplies other

parameters needed by system- and application-level software.

HP-UX workstations can run DHCP clients automatically. Autoparms

script enables HP-UX to run DHCP clients automatically. If you edit the

conﬁguration, the autoparms script will not run.

DHCP clients can include TCP/IP network printers, X terminals, and

Microsoft Windows machines. In addition to supporting new DHCP

clients, the HP-UX DHCP server supports new and existing BOOTP

clients.

DHCP clients are currently supported on 10 BaseT and 100 BaseT

ethernets. It is not supported on FDDI and Token Ring networks.