Allied Telesis AT-8100 Series - Manual (Page 654)

Chapter 44: DHCP Snooping Commands
654
IP DHCP SNOOPING DELETE-BY-LINKDOWN
Syntax
ip dhcp snooping delete-by-linkdown
Parameters
None
Mode
Global Configuration mode
Description
Use this command to set the switch to remove a dynamic entry from the
DHCP snooping database when its port goes down. If the port is part of an
aggregated link, the entries in the database are deleted only when all of
the ports in the aggregated link are down.
If this command is enabled in a stack, and the master switch goes down
and is replaced by a new master switch, entries in the DHCP snooping
database for ports on the master are removed. There is one exception. If
this command is enabled in a stack, and the master switch goes down and
is replaced by a new master switch, entries in the database for ports on
the master are not removed if they are part of link aggregators that are still
up.
By default, this command is disabled. With this setting, the DHCP
snooping bindings are not deleted when an interface goes down.
Use the no version of the command, the NO IP DHCP SNOOPING
DELETE-BY-LINKDOWN command, to set the switch to not delete entries
when ports go down.
Confirmation Command
“SHOW RUNNING-CONFIG” on page 170
Example
This example sets the switch to delete DHCP snooping lease entries from
the DHCP snooping database when links go down:
awplus> enable
awplus# configure terminal
awplus(config)# ip dhcp snooping delete-by-linkdown