20-18
Catalyst 2975 Switch Software Configuration Guide
OL-19720-02
Chapter 20 Configuring DHCP Features and IP Source Guard Features
Configuring IP Source Guard
provision
global configuration 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
“Stack Offline Configuration” section on page 6-7
.
Enabling IP Source Guard
Begin in privileged EXEC mode.
To disable IP source guard with source IP address filtering, use the
no ip verify source
interface
configuration command.
To delete a static IP source binding entry, use the
no ip source
global configuration command.
This example shows how to enable IP source guard with source IP and MAC filtering on VLANs 10
and 11:
Switch#
configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Switch(config)#
interface gigabitethernet1/0/1
Switch(config-if)#
ip verify source port-security
Command
Purpose
Step 1
configure terminal
Enter global configuration mode.
Step 2
interface
interface-id
Specify the interface to be configured, and enter interface configuration
mode.
Step 3
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.
Step 4
exit
Return to global configuration mode.
Step 5
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.
Step 6
end
Return to privileged EXEC mode.
Step 7
show ip verify source
[
interface
interface-id
]
Verify the IP source guard configuration.
Step 8
show ip source binding
[
ip-address
]
[
mac-address
] [
dhcp-snooping
|
static
]
[
inteface
interface-id
] [
vlan
vlan-id
]
Display the IP source bindings on the switch, on a specific VLAN, or on
a specific interface.
Step 9
copy running-config startup-config
(Optional) Save your entries in the configuration file.
