Purpose
Command or Action
(Optional) Enables verification that the advertised
preference (in preference option) is greater than the
specified limit. If not specified, this check will be bypassed.
preference min limit
Example:
Device(config-dhcp-guard)# preference min 0
Step 4
(Optional) Enables verification that the advertised
preference (in preference option) is less than the specified
limit. If not specified, this check will be bypassed.
preference max limit
Example:
Device(config-dhcp-guard)# preference max 255
Step 5
(Optional) Specifies that this policy is being applied to
trusted ports. All DHCP guard policing will be disabled.
trusted-port
Example:
Step 6
Device(config-dhcp-guard)# trusted-port
Exits DHCP guard configuration mode and returns to
global configuration mode.
exit
Example:
Step 7
Device(config-dhcp-guard)# exit
Specifies an interface and enters interface configuration
mode.
interface type number
Example:
Step 8
Device(config)# interface GigabitEthernet 0/2/0
Puts an interface that is in Layer 3 mode into Layer 2 mode
for Layer 2 configuration.
switchport
Example:
Step 9
Device(config-if)# switchport
Attaches a DHCPv6 guard policy to an interface.
ipv6 dhcp guard
[
attach-policy policy-name
]
Example:
Step 10
Device(config-if)# ipv6 dhcp guard attach-policy
pol1
Exits interface configuration mode and returns to global
configuration mode.
exit
Example:
Step 11
Device(config-if)# exit
Specifies a VLAN and enters VLAN configuration mode.
vlan configuration vlan-id
Example:
Step 12
Device(config)# vlan configuration 1
Cisco Nexus 9000 Series NX-OS Security Configuration Guide, Release 9.x
381
Configuring IPv6 First Hop Security
Configuring DHCP—DHCPv6 Guard
