HP ProCurve 2500 manual 132

Port Usage Traffic Control and

Optimizing Port Usage Through Traffic Control and Port Trunking

Port Trunking

Enabling a Dynamic LACP Trunk Group. In the default port configura- tion, all ports on the switch are set to LACP passive. However, to enable the switch to automatically form a trunk group that is dynamic on both ends of the link, the ports on one end of a set of links must be LACP active. The ports on the other end can be either LACP active or LACP passive. This command enables the switch to automatically establish a (dynamic) LACP trunk group when the device on the other end of the link is configured for LACP passive.

Switch “A”		Switch “B”
with ports set		with ports set
to LACP		to LACP
passive (the		passive (the
default).		default).
	Dynamic LACP trunk cannot automatically form because both
	ends of the links are LACP passive.
	(In this case STP blocking is needed to prevent a loop.

Optimizing Through

Switch “A” with ports set to LACP active.

Switch “B” with ports set to LACP passive (the default).

Dynamic LACP trunk automatically forms because both ends of the links are LACP and at least one end is LACP active. (STP is not needed, and the clear advantages are increased bandwidth and fault-tolerance.

Figure 6-10. Example of Criteria for Automatically Forming a Dynamic LACP Trunk

Syntax: interface <port-list>lacp active

This example uses ports 5 and 6 to enable a dynamic LACP trunk group.

HP2512(config)# interface 5-6 lacp active

6-22