Default Dhcp Configuration; Dhcp Snooping Configuration Guidelines - Cisco ME 3400 Software Configuration Manual

Configuring DHCP Features
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Default DHCP Configuration

Table 19-1
Table 19-1 Default DHCP Configuration
Feature
DHCP server
DHCP relay agent
DHCP packet forwarding address
Checking the relay agent information
DHCP relay agent forwarding policy
DHCP snooping enabled globally
DHCP snooping information option
DHCP snooping option to accept packets on
untrusted ingress interfaces
DHCP snooping limit rate
DHCP snooping trust
DHCP snooping VLAN
DHCP snooping MAC address verification
Cisco IOS DHCP server binding database
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. Use this feature when the switch is an aggregation switch that receives packets with option-82 information from an edge switch.

DHCP Snooping Configuration Guidelines

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Cisco ME 3400 Ethernet Access Switch Software Configuration Guide
19-8
Enabling the Cisco IOS DHCP Server Database, page 19-13
Enabling the DHCP Snooping Binding Database Agent, page 19-14
shows the default DHCP configuration.
Default Setting
Enabled in Cisco IOS software, requires configuration
Enabled
None configured
Enabled (invalid messages are dropped)
Replace the existing relay agent information
Disabled
Enabled
Disabled
3
None configured
Untrusted
Disabled
Enabled
Enabled in Cisco IOS software, requires configuration.
Note
Enabled in Cisco IOS software, requires configuration. This feature is
operational only when a destination is configured.
You must globally enable DHCP snooping on the switch.
DHCP snooping is not active until DHCP snooping is enabled on a VLAN.
Before globally enabling DHCP snooping on the switch, make sure that the devices acting as the
DHCP server and the DHCP relay agent are configured and enabled.
Chapter 19
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The switch gets network addresses and configuration parameters
only from a device configured as a DHCP server.
Configuring DHCP Features and IP Source Guard
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