Cisco Catalyst 3550

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Catalyst 3550 Multilayer Switch Command Reference
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Chapter 2 Catalyst 3550 Switch Cisco IOS Commands
ip dhcp snooping information option format snmp-ifindex
ip dhcp snooping information option format snmp-ifindex
Use the ip dhcp snooping information option format snmp-ifindex global configuration command to
select the snmp-ifindex alternative option-82 data format. Use the no form of this command to use the
vlan-mod-port option-82 data format.
ip dhcp snooping information option format snmp-ifindex
no ip dhcp snooping information option format snmp-ifindex
Syntax Description This command has no arguments or keywords.
Defaults DHCP option-82 data insertion uses the vlan-mod-port format.
Command Modes Global configuration
Command History
Usage Guidelines If you have option 82 configured on the switch and you upgrade to Cisco IOS Release 12.1(19)EA1 or
later, the option
82 configuration is not affected. However, when you enable DHCP snooping globally
on the switch by using the ip dhcp snooping global configuration command, the relay agent
information option configuration is disabled. This happens regardless of whether snooping is enabled
on any VLANs. To provide for backward compatibility when using option 82 with DHCP snooping, you
can select the previous option-82 format by using the ip dhcp snooping information option format
snmp-ifindex global configuration command.
You can configure some switches in the network to continue using the previous option 82 format, and
configure DHCP snooping on other switches in the network.
Option-82 information is only inserted on snooped VLANs.
Examples This example shows how to enable DHCP option 82 data insertion in the snmp-ifindex format:
Switch(config)# ip dhcp snooping information option format snmp-ifindex
You can verify your settings by entering the show ip dhcp snooping privileged EXEC command.
Related Commands
Release Modification
12.1(19)EA1 This command was introduced.
Command Description
show ip dhcp snooping Displays the DHCP snooping configuration.
show ip dhcp snooping binding Displays the DHCP snooping binding information.
show ip dhcp snooping statistics Displays the DHCP snooping statistics in summary or detail
form.