Configuring Dhcp Features; Default Dhcp Configuration - Cisco WS-C3750-48PS-S Software Configuration Manual

Chapter 21 Configuring DHCP Features and IP Source Guard

Configuring DHCP Features

These sections describe how to configure the DHCP server, the DHCP relay agent, DHCP snooping,
option 82, the Cisco IOS DHCP server binding database, and the DHCP snooping binding database on
your switch:
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Default DHCP Configuration

Table 21-1
Table 21-1 Default DHCP Configuration
Feature
DHCP server
DHCP relay agent
DHCP packet forwarding address
Checking the relay agent information
DHCP relay agent forwarding policy
Cisco IOS DHCP server binding database
DHCP snooping enabled globally
DHCP snooping information option
DHCP snooping limit rate
DHCP snooping trust
DHCP snooping VLAN
DHCP snooping MAC address verification
DHCP snooping binding database agent
1. The switch responds to DHCP requests only if it is configured as a DHCP server.
2. The switch relays DHCP packets only if the IP address of the DHCP server is configured on the SVI of the DHCP client.
3. This feature is supported only when your switch is running the enhanced multilayer image (EMI).
4. The switch gets network addresses and configuration parameters only from a device configured as DHCP server.
78-16180-02
Default DHCP Configuration, page 21-7
DHCP Snooping Configuration Guidelines, page 21-8
Configuring the DHCP Server, page 21-8
DHCP Server and Switch Stacks, page 21-9
Configuring the DHCP Relay Agent, page 21-9
Specifying the Packet Forwarding Address, page 21-9
Enabling DHCP Snooping and Option 82, page 21-10
Enabling DHCP Snooping on Private VLANs, page 21-12
Enabling the Cisco IOS DHCP Server Database, page 21-12
Enabling the DHCP Snooping Binding Database Agent, page 21-12
shows the default DHCP configuration.
Default Setting
1
Enabled
2
Enabled
None configured
Enabled (invalid messages are dropped)
Replace the existing relay agent information
3 4
Enabled
Disabled
Enabled
None configured
Untrusted
Disabled
Enabled
3
Enabled
Catalyst 3750 Switch Software Configuration Guide
Configuring DHCP Features
2
2
21-7