Example 14 Internal statements used by Dynamic IP Lockdown
permit 10.0.8.5 001122-334455 vlan 2
permit 10.0.8.7 001122-334477 vlan 2
permit 10.0.10.3 001122-334433 vlan 5
permit 10.0.10.1 001122-110011 vlan 5
deny any vlan 2,5
permit any
Note that the
deny any
statement is applied only to VLANs for which DHCP snooping is enabled.
The
permit any
statement is applied only to all other VLANs.
Enabling dynamic IP lockdown
To enable dynamic IP lockdown globally on all ports or on specified ports on the routing switch,
enter the
ip source-lockdown
command at the global configuration level; use the
no
form of
the command to disable dynamic IP lockdown.
Syntax:
[
no
]
ip source-lockdown <port-list>
Detail
Task
Parameter
Separate individual port numbers or ranges of port
numbers with a comma (for example,
13-15, 17
).
Specifies a port number or
a range of port numbers.
port-list
Example:
HP Switch(config)# ip source—lockdown 5-8, 17
Dynamic IP lockdown is enabled at the port configuration level and applies to all bridged or routed
IP packets entering the switch. The only IP packets exempt from dynamic IP lockdown are broadcast
DHCP request packets, which are handled by DHCP snooping.
DHCP snooping is a prerequisite for Dynamic IP Lockdown operation. The following restrictions
apply:
•
DHCP snooping is required for dynamic IP lockdown to operate. To enable DHCP snooping,
enter the
dhcp-snooping
command at the global configuration level.
•
Dynamic IP lockdown only filters packets in VLANs that are enabled for DHCP snooping. For
Dynamic IP lockdown to work on a port, the port must be configured for at least one VLAN
that is enabled for DHCP snooping.
To enable DHCP snooping on a VLAN, enter the
dhcp-snooping vlan [vlan-id-range]
command at the global configuration level or the
dhcp-snooping
command at the VLAN
configuration level.
•
Dynamic IP lockdown is not supported on a trusted port. (However, note that the DHCP server
must be connected to a trusted port when DHCP snooping is enabled.)
By default, all ports are untrusted. To remove the trusted configuration from a port, enter the
no dhcp-snooping trust <port-list>
command at the global configuration level.
For more information on how to configure and use DHCP snooping, see
To enable IP lockdown:
22
Updates for the HP Switch Software Access Security Guide