C H A P T E R
1-1
Cisco ASA Series CLI Configuration Guide
1
Configuring DHCP
This chapter describes how to configure the DHCP server and includes the following sections:
•
Information About DHCP, page 1-1
•
Licensing Requirements for DHCP, page 1-2
•
Guidelines and Limitations, page 1-2
•
Configuring a DHCP Server, page 1-3
•
Configuring the DHCP Relay Service, page 1-8
•
Additional References, page 1-9
•
DHCP Monitoring Commands, page 1-10
•
Feature History for DHCP, page 1-10
Information About DHCP
The DHCP Relay Agent sends Dynamic Host Configuration Protocol (DHCP) messages between DHCP
clients and servers on different IP networks. DHCP provides network configuration parameters, such as
IP addresses, to DHCP clients. The ASA can provide a DHCP server or DHCP relay service to DHCP
clients attached to ASA interfaces. The DHCP server provides network configuration parameters
directly to DHCP clients. The DHCP relay service sends DHCP requests received on one interface to an
external DHCP server located on a different interface.
A client locates a DHCP server to request the assignment of configuration information using a reserved,
link-scoped multicast address, which indicates that the client and server should be attached to the same
link. However, in some cases where ease of management, economy, or scalability is the concern, we
recommend that you allow a DHCP client to send a message to a server that is not connected to the same
link. The DHCP relay agent, which may reside on the client network, can relay messages between the
client and server. The relay agent operation is transparent to the client.
DHCP for IPv6 (DHCPv6) specified in RFC 3315 enables IPv6 DHCP servers to send configuration
parameters such as network addresses or prefixes and DNS server addresses to IPv6 nodes (that is,
DHCP clients). DHCPv6 uses the following multicast addresses:
•
All_DHCP_Relay_Agents_and_Servers (FF02::1:2) is a link-scoped multicast address used by a
client to communicate with neighboring (that is, on-link) relay agents and servers. All DHCPv6
servers and relay agents are members of this multicast group.
•
The DHCPv6 relay service and server listen for messages on UDP port 547. The ASA DHCPv6 relay
agent listens on both UDP port 547 and the All_DHCP_Relay_Agents_and_Servers multicast
address.
Summary of Contents for 5505 - ASA Firewall Edition Bundle
Page 28: ...Glossary GL 24 Cisco ASA Series CLI Configuration Guide ...
Page 61: ...P A R T 1 Getting Started with the ASA ...
Page 62: ......
Page 219: ...P A R T 2 Configuring High Availability and Scalability ...
Page 220: ......
Page 403: ...P A R T 2 Configuring Interfaces ...
Page 404: ......
Page 499: ...P A R T 2 Configuring Basic Settings ...
Page 500: ......
Page 533: ...P A R T 2 Configuring Objects and Access Lists ...
Page 534: ......
Page 601: ...P A R T 2 Configuring IP Routing ...
Page 602: ......
Page 745: ...P A R T 2 Configuring Network Address Translation ...
Page 746: ......
Page 845: ...P A R T 2 Configuring AAA Servers and the Local Database ...
Page 846: ......
Page 981: ...P A R T 2 Configuring Access Control ...
Page 982: ......
Page 1061: ...P A R T 2 Configuring Service Policies Using the Modular Policy Framework ...
Page 1062: ......
Page 1093: ...P A R T 2 Configuring Application Inspection ...
Page 1094: ......
Page 1191: ...P A R T 2 Configuring Unified Communications ...
Page 1192: ......
Page 1333: ...P A R T 2 Configuring Connection Settings and QoS ...
Page 1334: ......
Page 1379: ...P A R T 2 Configuring Advanced Network Protection ...
Page 1380: ......
Page 1475: ...P A R T 2 Configuring Modules ...
Page 1476: ......
Page 1549: ...P A R T 2 Configuring VPN ...
Page 1550: ......
Page 1965: ...P A R T 2 Configuring Logging SNMP and Smart Call Home ...
Page 1966: ......
Page 2059: ...P A R T 2 System Administration ...
Page 2060: ......
Page 2098: ...1 8 Cisco ASA Series CLI Configuration Guide Chapter 1 Troubleshooting Viewing the Coredump ...
Page 2099: ...P A R T 2 Reference ...
Page 2100: ......