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Ip dhcp snooping vlan, Ip dhcp snooping vlan (4-319) – Accton Technology Edge-corE Fast Ethernet Switch ES3528M-SFP User Manual

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DHCP Snooping Commands

4-319

4

switch will not add a dynamic entry for itself to the binding table when it
receives an ACK message from a DHCP server. Also, when the switch sends
out DHCP client packets for itself, no filtering takes place. However, when the
switch receives any messages from a DHCP server, any packets received
from untrusted ports are dropped.

Example
This example enables DHCP snooping globally for the switch.

Related Commands

ip dhcp snooping vlan (4-319)
ip dhcp snooping trust (4-320)

ip dhcp snooping vlan

This command enables DHCP snooping on the specified VLAN. Use the no form to
restore the default setting.

Syntax

[no] ip dhcp snooping vlan vlan-id

vlan-id - ID of a configured VLAN (Range: 1-4094)

Default Setting

Disabled

Command Mode

Global Configuration

Command Usage

• When DHCP snooping enabled globally using the ip dhcp snooping

command (page 4-317), and enabled on a VLAN with this command, DHCP
packet filtering will be performed on any untrusted ports within the VLAN as
specified by the ip dhcp snooping trust command (page 4-320).

• When the DHCP snooping is globally disabled, DHCP snooping can still be

configured for specific VLANs, but the changes will not take effect until DHCP
snooping is globally re-enabled.

• When DHCP snooping is globally enabled, configuration changes for specific

VLANs have the following effects:
- If DHCP snooping is disabled on a VLAN, all dynamic bindings learned for

this VLAN are removed from the binding table.

Example
This example enables DHCP snooping for VLAN 1.

Console(config)#ip dhcp snooping
Console(config)#

Console(config)#ip dhcp snooping vlan 1
Console(config)#