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Cisco Catalyst Blade Switch 3030 Command Reference
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Chapter 2 Cisco Catalyst Blade Switch 3030 Cisco IOS Commands
ip dhcp snooping vlan information option format-type circuit-id string
ip dhcp snooping vlan information option format-type circuit-id
string
Use the
ip dhcp snooping vlan information option format-type circuit-id string
interface
configuration command on the switch to configure the option-82 circuit-ID suboption. Use the
no
form
of this command to configure the default circuit-ID suboption.
ip dhcp snooping vlan
vlan
information option format-type circuit-id string
ASCII-string
no ip dhcp snooping vlan
vlan
information option format-type circuit-id string
Syntax Description
Defaults
The switch VLAN and the port identifier, in the format
vlan-mod-port
, is the default circuit ID.
Command Modes
Interface configuration
Usage Guidelines
You must globally enable DHCP snooping by using the
ip dhcp snooping
global configuration
command for any DHCP snooping configuration to take effect.
When the option-82 feature is enabled, the default circuit-ID suboption is the switch VLAN and the port
identifier, in the format
vlan-mod-port
. This command allows you to configure a string of ASCII
characters to be the circuit ID.
Note
When configuring a large number of circuit IDs on a switch, consider the impact of lengthy character
strings on the NVRAM or flash memory. If the circuit-ID configurations, combined with other data,
exceed the capacity of the NVRAM or the flash memory, an error message appears.
Examples
This example shows how to configure the option-82 circuit-ID suboption:
Switch(config-if)#
ip dhcp snooping vlan 250 information option format-type circuit-id
string customerABC-250-0-0
You can verify your settings by entering the
show ip dhcp snooping
user EXEC command.
Note
The
show
ip dhcp snooping
user EXEC command only displays the global command output, including
a remote-ID configuration. It does not display any per-interface, per-VLAN string that you have
configured for the circuit ID.
vlan
vlan
Specify the VLAN ID. The range is 1 to 4094.
string
ASCII-string
Specify a circuit ID, using from 3 to 63 ASCII characters (no
spaces).