Specifications

Link Aggregation
Rev. 9.41 Module 4 – 117
Active and Passive LACP
LACP is disabled by default on HP ProCurve switches. When you enable LACP on a
port, you define it as active or passive.
BPDUs (bridge protocol data unit) are data messages that are exchanged across the
switches to detect loops in a network topology. BPDUs allow for switches to obtain
information about each other.
Ports set to active LACP transmit BPDUs to advertise that they can create trunks. Ports
set to passive LACP listen for BPDUs.
Three fields within the BPDU are relevant to LACP. These include:
 Priority value
 Switch MAC address
 Port identifier
For HP Internal Use Only