Prerequisites For Configuring Dhcp Snooping And Option 82 - Cisco Catalyst 2960-X Security Configuration Manual

Configuring DHCP
Command or Action
Step 8
switchport mode access
Example:
Switch(config-if)# switchport mode access
Step 9 switchport access vlan vlan-id
Example:
Switch(config-if)# switchport access vlan 1
Step 10 end
Example:
Switch(config-if)# end
Step 11
show running-config
Example:
Switch# show running-config
Step 12 copy running-config startup-config
Example:
Switch# copy running-config startup-config

Prerequisites for Configuring DHCP Snooping and Option 82

The prerequisites for DHCP Snooping and Option 82 are as follows:
• You must globally enable DHCP snooping on the switch.
• Before globally enabling DHCP snooping on the switch, make sure that the devices acting as the DHCP
• If you want the switch to respond to DHCP requests, it must be configured as a DHCP server.
• Before configuring the DHCP snooping information option on your switch, be sure to configure the
• For DHCP snooping to function properly, all DHCP servers must be connected to the switch through
OL-29048-01
server and the DHCP relay agent are configured and enabled.
device that is acting as the DHCP server. You must specify the IP addresses that the DHCP server can
assign or exclude, or you must configure DHCP options for these devices.
trusted interfaces. In a service-provider network, a trusted interface is connected to a port on a device
in the same network.
Catalyst 2960-X Switch Security Configuration Guide, Cisco IOS Release 15.0(2)EX
Prerequisites for Configuring DHCP Snooping and Option 82
Purpose
Defines the VLAN membership mode for the port.
Assigns the ports to the same VLAN as configured in Step 2.
Returns to privileged EXEC mode.
Verifies your entries.
(Optional) Saves your entries in the configuration file.
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