Cisco ASA 5505 - Manual (Page 349)

11-3
Cisco ASA 5500 Series Configuration Guide using the CLI
Chapter 11 Configuring DHCP
Configuring a DHCP Server
Enabling the DHCP Server
The ASA can act as a DHCP server. DHCP is a protocol that provides network settings to hosts, including
the host IP address, the default gateway, and a DNS server.
Note The ASA DHCP server does not support BOOTP requests. In multiple context mode, you cannot enable
the DHCP server or DHCP relay on an interface that is used by more than one context.
To enable the DHCP server on a ASA interface, perform the following steps:
Command Purpose
Step 1 dhcpd address ip_address-ip_address
interface_name
Example:
hostname(config)# dhcpd address
10.0.1.101-10.0.1.110 inside
Create a DHCP address pool. The ASA assigns a client one of the
addresses from this pool to use for a given length of time. These
addresses are the local, untranslated addresses for the directly
connected network.
The address pool must be on the same subnet as the ASA
interface.
Step 2 dhcpd dns dns1 [dns2]
Example:
hostname(config)# dhcpd dns 209.165.201.2
209.165.202.129
(Optional) Specifies the IP address(es) of the DNS server(s).
Step 3 dhcpd wins wins1 [wins2]
Example:
hostname(config)# dhcpd wins 209.165.201.5
(Optional) Specifies the IP address(es) of the WINS server(s).
You can specify up to two WINS servers.
Step 4 dhcpd lease lease_length
Example:
hostname(config)# dhcpd lease 3000
(Optional) Change the lease length to be granted to the client.
This lease equals the amount of time (in seconds) the client can
use its allocated IP address before the lease expires. Enter a value
between 0 to 1,048,575. The default value is 3600 seconds.
Step 5 dhcpd domain domain_name
Example:
hostname(config)# dhcpd domain example.com
(Optional) Configures the domain name.
Step 6 dhcpd ping_timeout milliseconds
Example:
hostname(config)# dhcpd ping timeout 20
(Optional) Configures the DHCP ping timeout value. To avoid
address conflicts, the ASA sends two ICMP ping packets to an
address before assigning that address to a DHCP client. This
command specifies the timeout value for those packets.