Cisco Catalyst 3750-E - Displaying Ip Source Guard Information

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Catalyst 3750-E and 3560-E Switch Software Configuration Guide
OL-9775-08
Chapter 22 Configuring DHCP Features and IP Source Guard
Displaying IP Source Guard Information
Switch(config-if)# ip device tracking maximum 8
Switch(config-if)# ip verify source tracking
Switch# show ip
device tracking all
IP Device Tracking = Enabled
IP Device Tracking Probe Count = 3
IP Device Tracking Probe Interval = 30
---------------------------------------------------------------------
IP Address MAC Address Vlan Interface STATE
---------------------------------------------------------------------
40.1.1.24 0000.0000.0304 200 GigabitEthernet1/0/3 ACTIVE
40.1.1.20 0000.0000.0305 200 GigabitEthernet1/0/3 ACTIVE
40.1.1.21 0000.0000.0306 200 GigabitEthernet1/0/3 ACTIVE
40.1.1.22 0000.0000.0307 200 GigabitEthernet1/0/3 ACTIVE
40.1.1.23 0000.0000.0308 200 GigabitEthernet1/0/3 ACTIVE
The output shows the five valid IP-MAC bindings that have been learned on the interface Fa0/3. For the
private VLAN cases, the bindings are associated with primary VLAN ID. So, in this example, the
primary VLAN ID, 200, is shown in the table.
Switch# show ip verify source
Interface Filter-type Filter-mode IP-address Mac-address Vlan
--------- ----------- ----------- --------------- ----------------- ----
Gi1/0/3 ip trk active 40.1.1.23 200
Gi1/0/3 ip trk active 40.1.1.24 200
Gi1/0/3 ip trk active 40.1.1.20 200
Gi1/0/3 ip trk active 40.1.1.21 200
Gi1/0/3 ip trk active 40.1.1.22 200
Gi1/0/3 ip trk active 40.1.1.23 201
Gi1/0/3 ip trk active 40.1.1.24 201
Gi1/0/3 ip trk active 40.1.1.20 201
Gi1/0/3 ip trk active 40.1.1.21 201
Gi1/0/3 ip trk active 40.1.1.22 201
The output shows that the five valid IP-MAC bindings are on both the primary and secondary VLAN.
Displaying IP Source Guard Information
Understanding DHCP Server Port-Based Address Allocation
DHCP server port-based address allocation is a feature that enables DHCP to maintain the same IP
address on an Ethernet switch port regardless of the attached device client identifier or client hardware
address.
When Ethernet switches are deployed in the network, they offer connectivity to the directly connected
d
evices. In some environments, such as on a factory floor, if a device fails, the replacement device must
be working immediately in the existing network. With the current DHCP implementation, there is no
Ta b l e 22-3 Commands for Displaying IP Source Guard Information
Command Purpose
show ip source binding Display the IP source bindings on a switch.
show ip verify source Display the IP source guard configuration on the switch.