Configuring The Dhcp Server; Configuring The Dhcp Relay Agent; Specifying The Packet Forwarding Address - Cisco ME 3400 Software Configuration Manual

Configuring DHCP Features

Configuring the DHCP Server

The switch can act as a DHCP server. By default, the Cisco IOS DHCP server and relay agent features
are enabled on your switch but are not configured. These features are not operational.
For procedures to configure the switch as a DHCP server, see the "Configuring DHCP" section of the
"IP addressing and Services" section of the Cisco IOS IP Configuration Guide, Release 12.2.

Configuring the DHCP Relay Agent

Beginning in privileged EXEC mode, follow these steps to enable the DHCP relay agent on the switch:
Command
Step 1 configure terminal
Step 2 service dhcp
Step 3 end
Step 4
show running-config
Step 5 copy running-config startup-config
To disable the DHCP relay agent, use the no service dhcp global configuration command.
See the "Configuring DHCP" section of the "IP Addressing and Services" section of the Cisco IOS IP
Configuration Guide, Release 12.2 for these procedures:
•
•

Specifying the Packet Forwarding Address

If the DHCP server and the DHCP clients are on different networks or subnets and the switch is running
the metro IP access image, you must configure the switch with the ip helper-address address interface
configuration command. The general rule is to configure the command on the Layer 3 interface closest
to the client. The address used in the ip helper-address command can be a specific DHCP server IP
address, or it can be the network address if other DHCP servers are on the destination network segment.
Using the network address enables any DHCP server to respond to requests.
Beginning in privileged EXEC mode, follow these steps to specify the packet forwarding address:
Command
Step 1 configure terminal
Step 2 interface vlan vlan-id
Step 3 ip address ip-address subnet-mask
Cisco ME 3400 Ethernet Access Switch Software Configuration Guide
19-10
Purpose
Enter global configuration mode.
Enable the DHCP relay agent on your switch. By default, this feature is
enabled.
Return to privileged EXEC mode.
Verify your entries.
(Optional) Save your entries in the configuration file.
Checking (validating) the relay agent information
Configuring the relay agent forwarding policy
Chapter 19 Configuring DHCP Features and IP Source Guard
Purpose
Enter global configuration mode.
Create a switch virtual interface by entering a VLAN
ID, and enter interface configuration mode.
Configure the interface with an IP address and an IP
subnet.
OL-9639-07