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Catalyst 3750 Metro Switch Command Reference
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Chapter 2 Catalyst 3750 Metro Switch 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
[
override
]
string
ASCII-string
no ip dhcp snooping vlan
vlan
information option format-type circuit-id
[
override
]
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
Command History
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 port
identifier, in the format
vlan-mod-port
. This command allows you to configure a string of ASCII
characters to be the circuit ID. When you want to override the
vlan-mod-port
format type and instead
use the circuit-ID to define subscriber information, use the
override
keyword.
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 flash memory, an error message appears.
vlan
vlan
Specify the VLAN ID. The range is 1 to 4094.
override
(Optional) Specify an override string, using from 3 to 63 ASCII
characters (no spaces).
string
ASCII-string
Specify a circuit ID, using from 3 to 63 ASCII characters (no
spaces).
Release
Modification
12.2(25)SEE
This command was introduced.
12.2(52)SE
The
override
keyword was added.