C H A P T E R 11
Configuring DHCP, DDNS, and WCCP Services
This chapter describes how to configure the DHCP server, dynamic DNS (DDNS) update methods, and
WCCP on the security appliance. DHCP provides network configuration parameters, such as IP
addresses, to DHCP clients. The security appliance can provide a DHCP server or DHCP relay services
to DHCP clients attached to security appliance interfaces. The DHCP server provides network
configuration parameters directly to DHCP clients. DHCP relay passes DHCP requests received on one
interface to an external DHCP server located behind a different interface.
DDNS update integrates DNS with DHCP. The two protocols are complementary: DHCP centralizes and
automates IP address allocation; DDNS update automatically records the association between assigned
addresses and hostnames at pre-defined intervals. DDNS allows frequently changing address-hostname
associations to be updated frequently. Mobile hosts, for example, can then move freely on a network
without user or administrator intervention. DDNS provides the necessary dynamic updating and
synchronizing of the name to address and address to name mappings on the DNS server.
WCCP specifies interactions between one or more routers, Layer 3 switches, or security appliances and
one or more web caches. The feature transparently redirects selected types of traffic to a group of web
cache engines to optimize resource usage and lower response times.
The security appliance does not support QIP DHCP servers for use with DHCP Proxy.
This chapter includes the following sections:
• Configuring a DHCP Server, page 11-1
• Configuring DHCP Relay Services, page 11-5
• Configuring Dynamic DNS, page 11-6
• Configuring Web Cache Services Using WCCP, page 11-10
Configuring a DHCP Server
This section describes how to configure DHCP server provided by the security appliance. This section
includes the following topics:
• Enabling the DHCP Server, page 11-2
• Configuring DHCP Options, page 11-3