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Cisco 7600 Series Router Cisco IOS Software Configuration Guide, Release 12.2SX
OL-4266-08
Chapter 37 Configuring DHCP Snooping
Configuring DHCP Snooping
------------------ --------------- ---------- ------------- ---- --------------------
00:01:00:01:00:05 1.1.1.1 49810 dhcp-snooping 512 GigabitEthernet1/1
00:01:00:01:00:02 1.1.1.1 49810 dhcp-snooping 512 GigabitEthernet1/1
00:01:00:01:00:04 1.1.1.1 49810 dhcp-snooping 1536 GigabitEthernet1/1
00:01:00:01:00:03 1.1.1.1 49810 dhcp-snooping 1024 GigabitEthernet1/1
00:01:00:01:00:01 1.1.1.1 49810 dhcp-snooping 1 GigabitEthernet1/1
Router#
clear ip dhcp snoop bind
Router#
show ip dhcp snoop bind
MacAddress IpAddress Lease(sec) Type VLAN Interface
------------------ --------------- ---------- ------------- ---- --------------------
Router#
Example 3: Adding Information to the DHCP Snooping Database
To manually add a binding to the DHCP snooping database, perform the following task:
This example shows how to manually add a binding to the DHCP snooping database:
Router#
show ip dhcp snooping binding
MacAddress IpAddress Lease(sec) Type VLAN Interface
------------------ --------------- ---------- ------------- ---- --------------------
Router#
Router#
ip dhcp snooping binding 1.1.1 vlan 1 1.1.1.1 interface gi1/1 expiry 1000
Router#
show ip dhcp snooping binding
MacAddress IpAddress Lease(sec) Type VLAN Interface
------------------ --------------- ---------- ------------- ---- --------------------
00:01:00:01:00:01 1.1.1.1 992 dhcp-snooping 1 GigabitEthernet1/1
Router#
Displaying a Binding Table
The DHCP snooping binding table for each router contains binding entries that correspond to untrusted
ports. The table does not contain information about hosts interconnected with a trusted port because each
interconnected router will have its own DHCP snooping binding table.
This example shows how to display the DHCP snooping binding information for a router:
Router#
show ip dhcp snooping binding
MacAddress IpAddress Lease(sec) Type VLAN Interface
------------------ --------------- ---------- ------------- ---- --------------------
00:02:B3:3F:3B:99 55.5.5.2 6943 dhcp-snooping 10 FastEthernet6/10
Table 37-2
describes the fields in the
show ip dhcp snooping binding
command output.
Command
Purpose
Step 1
Router#
show ip dhcp snooping binding
Views the DHCP snooping database.
Step 2
Router#
ip dhcp snooping binding
binding_id
vlan
vlan_id
interface
interface
expiry
lease_time
Adds the binding using the
ip dhcp snooping
exec
command.
Step 3
Router#
show ip dhcp snooping binding
Checks the DHCP snooping database.