Reference Guide

Command History
This guide is platform-specific. For command information about other platforms, refer to the
relevant FTOS Command Line Reference Guide .
The following is a list of the FTOS version history for this command.
Version 9.2.(0.0) Introduced on the S4810 and S4820T.
Version 8.3.11.1 Introduced on the Z9000.
Version 8.3.1.0 Introduced on the E-Series.
Version 8.2.1.0 Introduced on the C-Series and S-Series on Layer 2 interfaces.
Version 7.8.1.0 Introduced on the C-Series and S-Series on Layer 3 interfaces.
Usage
Information
When enabled, no learning takes place until you enable snooping on a VLAN. After disabling
DHCP snooping, the binding table deletes and Option 82, IP Source Guard, and Dynamic ARP
Inspection are disabled.
Introduced in FTOS version 7.8.1.0, DHCP snooping was available for Layer 3 only and
dependent on DHCP Relay Agent (ip helper-address). FTOS version 8.2.1.0 extends
DHCP Snooping to Layer 2. You do not have to enable relay agent to snoop on Layer 2
interfaces.
Related
Commands
ip dhcp snooping vlan — enables DHCP snooping on one or more VLANs.
ip dhcp snooping binding
Create a static entry in the DHCP binding table.
S4820T
Syntax
[no] ip dhcp snooping binding mac address vlan-id vlan-id ip
ip-address interface type slot/port lease number
Parameters
mac address Enter the keyword mac then the MAC address of the host to which
the server is leasing the IP address.
vlan-id vlan-id Enter the keywords vlan-id then the VLAN to which the host
belongs. The range is from 2 to 4094.
ip ip-address Enter the keyword ip then the IP address that the server is leasing.
interface type Enter the keyword interface then the type of interface to which
the host is connected:
• For an 10/100 Ethernet interface, enter the keyword
fastethernet.
• For a Gigabit Ethernet interface, enter the keyword
gigabitethernet.
• For a SONET interface, enter the keyword sonet.
• For a Ten-Gigabit Ethernet interface, enter the keyword
tengigabitethernet.
• For a 40-Gigabit Ethernet interface, enter the keyword
fortyGigE.
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