Clearing DHCP Snooping Binding Entries

Context

After the networking environment changes, DHCP snooping binding entries do not age immediately. The following information in DHCP snooping binding entries may change, causing packet forwarding failure:

VLAN to which a DHCP client belongs.
Interface to which DHCP clients are connected.

Before changing the networking environment, clear all DHCP snooping binding entries manually so that the device generates a new DHCP snooping binding table based on the new networking environment.

After the DHCP snooping binding entries are cleared, network communication can be recovered only after all the DHCP users connected to the device re-log in and new binding entries are generated. Exercise caution when you run the command.

Procedure

In the user view, run the following commands to clear DHCP snooping binding entries:
- reset dhcp snooping user-bind [ vlan vlan-id | interface interface-type interface-number ] ^* [ ipv4 | ipv6 ]
- reset dhcp snooping user-bind [ ip-address [ ip-address ] | ipv6-address [ ipv6-address ] | vpls vpls-name ]
- reset dhcp snooping user-bind bridge-domain bd-id
- reset dhcp snooping user-bind [ ipv6-prefix [ prefix/prefix-length ] ]
Only the S5720-HI, S5730-HI, S5731-H, S5731S-H, S5732-H, S6730-H, S6730S-H, and S6720-HI support vpls parameter.

Only the S5720-HI, S5730-HI, S6720-HI, S6730-H, S6730S-H, S6730-S, S6730S-S, S5732-H, S5731-S, S5731S-S, S5731S-H, S5731-H, S6720-EI, and S6720S-EI support the bridge-domain parameter.