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Cisco IE 2000 Switch Software Configuration Guide
OL-25866-01
Chapter 25 Configuring DHCP
How to Configure DHCP
Enabling DHCP Snooping and Option 82
Step 6
interface range port-range
or
interface interface-id
Configures multiple physical ports that are connected
to the DHCP clients, and enters interface range
configuration mode.
or
Configures a single physical port that is connected to
the DHCP client, and enters interface configuration
mode.
Step 7
switchport mode access Defines the VLAN membership mode for the port.
Step 8
switchport access vlan vlan-id Assigns the ports to the same VLAN as configured in
Step 2.
Step 9
end Returns to privileged EXEC mode.
Command Purpose
Step 1
configure terminal Enters global configuration mode.
Step 2
ip dhcp snooping Enables DHCP snooping globally.
Step 3
ip dhcp snooping vlan vlan-range Enables DHCP snooping on a VLAN or range of VLANs. The range is
1
to 4096.
You can enter a single VLAN ID identified by VLAN ID number, a series
of VLAN IDs separated by commas, a range of VLAN IDs separated by
hyphens, or a range of VLAN IDs separated by entering the starting and
ending VLAN IDs separated by a space.
Step 4
ip dhcp snooping information option Enables the switch to insert and to remove DHCP relay information
(option-82 field) in forwarded DHCP request messages to the DHCP
server. This is the default setting.
Step 5
ip dhcp snooping information option
format remote-id [string ASCII-string |
hostname]
(Optional) Configures the remote-ID suboption.
You can configure the remote ID as
• String of up to 63 ASCII characters (no spaces)
• Hostname for the switch
Note If the hostname is longer than 63 characters, it is truncated to 63
characters in the remote-ID configuration.
The default remote ID is the switch MAC address.
Step 6
ip dhcp snooping information option
allow-untrusted
(Optional) If the switch is an aggregation switch connected to an edge
switch, enable the switch to accept incoming DHCP snooping packets
with option-82 information from the edge switch.
The default setting is disabled.
Note Enter this command only on aggregation switches that are
connected to trusted devices.
Command Purpose
