Users Guide

Layer 2 Switching Commands 545
If the device entry is modified during that delay interval, the initial probe
delay timer is canceled and the probe retransmit timer is started. Whenever
the device entry is updated from ARP Snooping or DHCP Snooping, the
probe retransmit timer is restarted.
Entries in the IPDT table are added on the following events:
• ARP snooping detected a new device.
• DHCP snooping issued a new address binding.
• Device entries detected by DHCP snooping are added into the IPDT table
even though the interface is in INACTIVE state. This can happen when
the interface is in the process of authorization.
Entries in the table are deleted on the following operations/events:
• ARP snooping detected a new device.
• DHCP snooping issued a new address binding.
• Device entries detected by DHCP snooping are added into the IPDT table
even though the interface is in INACTIVE state. This can happen when
the interface is in the process of authorization.
Entries in the table are deleted on the following operations/events:
• Administratively disabling the IPDT feature.
• A clear command is issued by the administrator.
• The interface on which the entries are learned is either detached or
deleted.
• The interface on which the entries are learned is enabled for port-based
routing.
• If interface is no longer member of a VLAN, the entries matching that
VLAN and interface are removed.
• When the entry is in inactive state for 72 hours.
• When the IPDT table capacity is reached, all the INACTIVE entries
learned from ARP snooping are deleted. Also, entries learned from DHCP
snooping are deleted if they are not present in the DHCP snooping
database.
Entries in the IPDT table are moved from ACTIVE to INACTIVE on the
following events: