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Dhcp snooping commands, Ip dhcp snooping, Table 4-85 – Accton Technology Edge-corE Fast Ethernet Switch ES3528M-SFP User Manual

Page 613: Ip dhcp snooping (4-317)

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DHCP Snooping Commands

4-317

4

Example

DHCP Snooping Commands

DHCP snooping allows a switch to protect a network from rogue DHCP servers or
other devices which send port-related information to a DHCP server. This
information can be useful in tracking an IP address back to a physical port. This
section describes commands used to configure DHCP snooping.

ip dhcp snooping

This command enables DHCP snooping globally. Use the no form to restore the
default setting.

Syntax

[no] ip dhcp snooping

Default Setting

Disabled

Command Mode

Global Configuration

Command Usage

• Network traffic may be disrupted when malicious DHCP messages are

received from an outside source. DHCP snooping is used to filter DHCP

Console#show ip source-guard binding
MacAddress IpAddress Lease(sec) Type VLAN Interface
----------------- --------------- ---------- -------------------- ---- ---------
11-22-33-44-55-66 192.168.0.99 0 Static 1 Eth 1/5
Console#

Table 4-85 DHCP Snooping Commands

Command

Function

Mode

Page

ip dhcp snooping

Enables DHCP snooping globally

GC

4-317

ip dhcp snooping vlan

Enables DHCP snooping on the specified VLAN

GC

4-319

ip dhcp snooping trust

Configures the specified interface as trusted

IC

4-320

ip dhcp snooping verify

mac-address

Verifies the client’s hardware address stored in the DHCP

packet against the source MAC address in the Ethernet header

GC

4-321

ip dhcp snooping

information option

Enables or disables DHCP Option 82 information relay

GC

4-321

ip dhcp snooping

information policy

Sets the information option policy for DHCP client packets that

include Option 82 information

GC

4-322

ip dhcp snooping

database flash

Writes all dynamically learned snooping entries to flash

memory

GC

4-323

show ip dhcp snooping Shows the DHCP snooping configuration settings

PE

4-323

show ip dhcp snooping

binding

Shows the DHCP snooping binding table entries

PE

4-324