clear dhcp-snooping binding
Syntax
clear dhcp-snooping binding [all | ip <IP-ADDR> | port <PORT-NUM> | vlan <VLAN-ID>]
Description
Clear all DHCP snooping binding entries or the binding entries on the specified IP address, port, or VLAN.
Parameters
- port <PORT-NUM>
Clear the DHCP snooping binding entries on the specified port by entering the port number.
- vlan <VLAN-ID>
Clear the DHCP snooping binding entries on the specified VLAN by entering the VLAN identifier.
Usage
clear dhcp-snooping binding allclear dhcp-snooping binding ip <IP-ADDR>r
clear dhcp-snooping binding VLAN <VLAN-ID>r
Example
switch(config)# clear dhcp-snooping binding all
Warning: Execution of this command results in clearing of dynamically learnt
DHCP Snooping entries from the binding table on this switch. Since the
DHCP Server and the DHCP Clients would not be aware of this change, this can
have side effects.
Do you want to continue (y/n)? y
switch(config)# sh dhcp-snooping binding
MacAddress IP VLAN Interface Time Left
------------- --------------- ---- --------- ---------
switch(config)# show log -r
Keys: W=Warning I=Information
M=Major D=Debug E=Error
---- Reverse event Log listing: Events Since Boot ----
W 12/12/16 14:27:03 05357 dhcp-snoop: AM1: All the dynamic binding entries were cleared.
I 12/12/16 14:23:24 03125 mgr: AM1: Startup configuration changed by CLI. New seq. number 7
Example
switch(config)# clear dhcp-snooping binding all
Warning: Execution of this command results in clearing of dynamically learnt
DHCP Snooping entries from the binding table on this switch. Since the
DHCP Server and the DHCP Clients would not be aware of this change, this can
have side effects.
Do you want to continue (y/n)? y
switch(config)# sh dhcp-snooping binding
MacAddress IP VLAN Interface Time Left
------------- --------------- ---- --------- ---------
switch(config)# show log -r
Keys: W=Warning I=Information
M=Major D=Debug E=Error
---- Reverse event Log listing: Events Since Boot ----
W 12/12/16 14:27:03 05357 dhcp-snoop: AM1: All the dynamic binding entries were cleared.
I 12/12/16 14:23:24 03125 mgr: AM1: Startup configuration changed by CLI. New seq. number 7
———————————————————————————————————————————————————————————————————————————————————————————————
switch(config)# show dhcp-snooping
DHCP Snooping Information
DHCP Snooping : Yes
Enabled VLANs : 20 40
Verify MAC address : Yes
Option 82 untrusted policy : drop
Option 82 insertion : Yes
Option 82 remote-id : mac
Store lease database : Not configured
Max Current Bindings
Port Trust Bindings Static Dynamic
----- ----- -------- ----------------
A1 Yes - - -
A2 No - - 10
Ports A3-A24,B1-B24,C1-C24,F1-F24 are untrusted
———————————————————————————————————————————————————————————————————————————————————————————————
switch(config)# show dhcp-snooping binding
MacAddress IP VLAN Interface Time Left
------------- --------------- ---- --------- ---------
000000-c97c83 192.168.101.21 20 A2 3579
000000-c97c84 192.168.101.30 20 A2 3582
000000-c97c85 192.168.101.28 20 A2 3579
000000-c97c86 192.168.101.25 20 A2 3577
000000-c97c87 192.168.101.23 20 A2 3574
000000-c97c88 192.168.101.26 20 A2 3579
000000-c97c89 192.168.101.24 20 A2 3580
000000-c97c8a 192.168.101.27 20 A2 3582
000000-c97c8b 192.168.101.29 20 A2 3577
000000-c97c8c 192.168.101.22 20 A2 3580
———————————————————————————————————————————————————————————————————————————————————————————————
switch(config)# show dhcp-snooping binding
MacAddress IP VLAN Interface Time Left
------------- --------------- ---- --------- ---------
switch(config)# show log -r
Keys: W=Warning I=Information
M=Major D=Debug E=Error
---- Reverse event Log listing: Events Since Boot ----
W 12/12/16 14:32:28 05359 dhcp-snoop: AM1: Dynamic binding entries on the port A2 were cleared.
W 12/12/16 14:29:58 05360 dhcp-snoop: AM1: Dynamic binding entries on the VLAN 20 were cleared.
W 12/12/16 14:29:36 05360 dhcp-snoop: AM1: Dynamic binding entries on the VLAN 40 were cleared.
W 12/12/16 14:28:29 00861 dhcp-snoop: AM1: backplane: Ceasing bad release logs for 5m
W 12/12/16 14:28:29 00860 dhcp-snoop: AM1: backplane: Attempt to release address
192.168.101.30 leased to port A2 detected on port A2
W 12/12/16 14:28:29 00860 dhcp-snoop: AM1: backplane: Attempt to release address
192.168.101.21 leased to port A2 detected on port A2
W 12/12/16 14:27:03 05357 dhcp-snoop: AM1: All the dynamic binding entries were cleared.
I 12/12/16 14:23:24 03125 mgr: AM1: Startup configuration changed by CLI. New seq. number 7
W 12/12/16 14:22:53 00853 dhcp-snoop: AM1: backplane: Ceasing untrusted port
destination logs for 5m
W 12/12/16 14:22:53 00852 dhcp-snoop: AM1: backplane: Client packet destined to
untrusted port dropped