Cisco Catalyst 2960 Series, Configuration Manual

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Purpose Command or Action
Assigns the ports to the same VLAN as configured in Step 2. switchport access vlan vlan-id
Example:
Switch(config-if)# switchport access vlan 1
Step 9
Returns to privileged EXEC mode. end
Example:
Switch(config-if)# end
Step 10
Verifies your entries. show running-config
Example:
Switch# show running-config
Step 11
(Optional) Saves your entries in the configuration file.
copy running-config startup-config
Example:
Switch# copy running-config startup-config
Step 12
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
server and the DHCP relay agent are configured and enabled.
• 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
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.
• For DHCP snooping to function properly, all DHCP servers must be connected to the switch through
trusted interfaces. In a service-provider network, a trusted interface is connected to a port on a device
in the same network.
• You must configure the switch to use the Cisco IOS DHCP server binding database to use it for DHCP
snooping.
• To use the DHCP snooping option of accepting packets on untrusted inputs, the switch must be an
aggregation switch that receives packets with option-82 information from an edge switch.
Consolidated Platform Configuration Guide, Cisco IOS Release 15.2(4)E (Catalyst 2960-X Switches)
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How to Configure DHCP Features