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Catalyst 6500 Series Switch Command Reference—Release8.4
OL-6244-01
Chapter2 Catalyst 6500 Series Switch and ROM Monitor Commands
set dhcp-snooping
set dhcp-snooping
To enable DHCP snooping information-option host tracking or the MAC address matching feature, use
the set dhcp-snooping command.
set dhcp-snooping information-option host-tracking {enable | disable}
set dhcp-snooping match-mac {enable | disable}
Syntax Description
Defaults Host tracking is disabled.
MAC address matching is enabled.
Command Types Switch command.
Command Modes Privileged.
Usage Guidelines The set dhcp-snooping information-option host-tracking {enable | disable} command enables or
disables host tracking. Enabling host tracking causes the DHCP snooping process to insert the relay
information agent option (option 82) with remote ID and circuit ID suboptions in all client-to-server
DHCP packets on VLANs for which DHCP snooping is enabled. E nabli ng host tra cki ng al so activates
the processing of option 82 in received server-to-client packets.
The set dhcp-snooping match-mac {enable | disable} command enables or disables the MAC address
matching feature. When this option is enabled, th e source MAC address i n t he Et herne t h ea de r i s
matched with the “chaddr” field in the DHCP payload for DHCP packets that com e from untrusted ports.
If the MAC address and “chaddr” field do not match, packets are dropped, and the counte r f or d roppe d
packets on untrusted ports is incremented.
If DHCP snooping is disabled on a VLAN, the bindings for that VLAN are deleted.
Examples This example shows how to enable DHCP snooping information-optio n h ost t rac king :
Console> (enable) set dhcp-snooping information-option host-tracking enable
DHCP Snooping Information Option Enabled.
Console> (enable)
information-option Specifies the DHCP information option feature.
host-tracking Specifies host tracking.
enable Enables the DHCP snooping feature.
disable Disables the DHCP snooping feature.
match-mac Specifies the DHCP snooping MAC address matching feature.