Cisco 300 Series User Manual

IPv6 First Hop Security
OL-32830-01 Command Line Interface Reference Guide 506
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Default Configuration
Verification is disabled.
Command Mode
Global Configuration mode
User Guidelines
This command enables verification that the preference value in messages sent by
DHCPv6 servers messages (see RFC3315) is greater than or less than the
value
argument.
Note. When DHCPv6 Guard receives a RELAY-REPL message, it takes it from the
encapsulated message.
Configuring the minimum
value keyword and argument specifies the minimum
allowed value. The received DHCPv6 reply message with a preference value less
than a value specified by the value
argument is dropped.
Configuring the maximum value keyword and argument specifies the maximum
allowed value. The received DHCPv6 reply message with a preference value
greater than the value specified by the value
argument is dropped.
Use no ipv6 dhcp guard preference to disable verification of the advertised
preference value in DHCPv6 reply messages.
Use no ipv6 dhcp guard preference maximum to disable verification of the
maximum boundary of the value of the advertised preference value in DHCPv6
messages.
Use the no ipv6 dhcp guard preference minimum command to disable verification
of the minimum boundary of the value of the advertised preference value in
DHCPv6 messages.
Examples
Example 1—The following example defines a global minimum preference value of
10 and a global maximum preference value of 102 using two commands:
switchxxxxxx(config)# ipv6 dhcp guard preference minimum 10
switchxxxxxx(config)# ipv6 dhcp guard preference maximum 102

Cisco 300 Series Specifications

General

Model	Cisco 300 Series
Category	Switch
Dimensions	Varies by model
Weight	Varies by model
Power over Ethernet (PoE)	Available on select models
Management	Web-based GUI, SNMP, CLI
VLANs	Up to 256
Security Features	ACLs, 802.1X, Port Security
Humidity	10% to 90% non-condensing
Ports	8, 16, 24, 48