General Security Measures

4-135

4
Additional considerations when the switch itself is a DHCP client – The port(s)
through which it submits a client request to the DHCP server must be
configured as trusted.
Example
This example sets port 5 to untrusted.
Related Commands
ip dhcp snooping (4-132)
ip dhcp snooping vlan (4-133)

ip dhcp snooping verify mac-address

This command verifies the client’s hardware address stored in the DHCP packet
against the source MAC address in the Ethernet header. Use the no form to disable
this function.
Syntax
[no] ip dhcp snooping verify mac-address
Default Setting
Enabled
Command Mode
Global Configuration
Command Usage
If MAC address verification is enabled, and the source MAC address in the
Ethernet header of the packet is not same as the client’s hardware address in
the DHCP packet, the packet is dropped.
Example
This example enables MAC address verification.
Related Commands
ip dhcp snooping (4-132)
ip dhcp snooping vlan (4-133)
ip dhcp snooping trust (4-134)
Console(config)#interface ethernet 1/5
Console(config-if)#no ip dhcp snooping trust
Console(config-if)#
Console(config)#ip dhcp snooping verify mac-address
Console(config)#