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Cisco Catalyst Blade Switch 3130 for Dell Software Configuration Guide
OL-13270-01
Chapter21 Configuring DHCP Features and IP Source Guard
Configuring IP Source Guard
When configuring IP source guard on interfaces on which a private VLAN is configured, port
security is not supported.
IP source guard is not supported on EtherChannels.
You can enable this feature when IEEE 802.1x port-based authentication is enabled.
If the number of hardware entries exceeds the maximum available, the CPU usage increases.
In a switch stack, if IP source guard is configured on a stack member interface and you remove the
the configuration of that switch by entering the no switch stack-member-number provision global
configuration command, the interface static bindings are removed fr om the bin di ng tab le, but they
are not removed from the running configuration. If you again provision the switch by entering the
switch stack-member-number provision command, the binding is restored.
To remove the binding from the running configuration, you must disable IP source guard bef or e
entering the no switch provision command. The configuration is also removed if the switch reloads
while the interface is removed from the binding table. For more information about provisioned
switches, see the Chapter5 , “ M an agi n g Sw it ch St a ck s.”
Enabling IP Source Guard
Beginning in privileged EXEC mode, follow these steps to enable and configure IP sourc e gua rd on an
interface.
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 interface interface-id Specify the interface to be configured, and enter interface configuration
mode.
Step3 ip verify source
or
ip verify source port-security
Enable IP source guard with source IP address filtering.
Enable IP source guard with source IP and MAC address filtering.
Note When you enable both IP Source Guard and Port Security by
using the ip verify source port-security interface configuration
command, there are two caveats:
The DHCP server must support option 82, or the client is not
assigned an IP address.
The MAC address in the DHCP packet is not learned as a secure
address. The MAC address of the DHCP client is learned as a
secure address only when the switch receives non-DHCP data
traffic.
Step4 exit Return to global configuration mode.
Step5 ip source binding mac-address vlan
vlan-id ip-address inteface interface-id Add a static IP source binding.
Enter this command for each static binding.
Step6 end Return to privileged EXEC mode.
Step7 show ip verify source [interface
interface-id]Display the IP source guard configuration for all interfaces or for a
specific interface.