Port Trunk Features And Operation; Fault Tolerance; Trunk Configuration Methods; Dynamic Lacp Trunk - HP Aruba JL253A Management And Configuration Manual

Port trunk features and operation

The switches covered in this guide offer these options for port trunking:
• LACP: IEEE 802.3ad—Trunk group operation using LACP on page 142
• Trunk: Non-Protocol—Trunk group operation using the "trunk" option on page 149
Up to 60 trunk groups are supported on the switches. The actual maximum depends on the number of ports
available on the switch and the number of links in each trunk. (Using the link aggregation control protocol—LACP
—option, you can include standby trunked ports in addition to the maximum of eight actively trunking ports.) The
trunks do not have to be the same size; For example, 100 two-port trunks and 11 eight-port trunks are supported.
NOTE: LACP requires full-duplex (FDx) links of the same media type (10/100Base-T, 100FX, and so
on) and the same speed, and enforces speed and duplex conformance across a trunk group. For
most installations, Hewlett Packard Enterprise Switch recommends that you leave the port Mode
settings at Auto (the default). LACP also operates with Auto-10, Auto-100, and Auto-1000 (if
negotiation selects FDx), and 10FDx, 100FDx, and 1000FDx settings. (The 10-gigabit ports
available for some switch models allow only the Auto setting.)

Fault tolerance

If a link in a port trunk fails, the switch redistributes traffic originally destined for that link to the remaining links in
the trunk. The trunk remains operable as long as there is at least one link in operation. If a link is restored, that
link is automatically included in the traffic distribution again. The LACP option also offers a standby link capability,
which enables you to keep links in reserve for service if one or more of the original active links fails. (See Trunk
group operation using LACP on page 142.)

Trunk configuration methods

Dynamic LACP trunk

The switch automatically negotiates trunked links between LACP-configured ports on separate devices, and offers
one dynamic trunk option: LACP. To configure the switch to initiate a dynamic LACP trunk with another device,
use the interface command in the CLI to set the default LACP option to active on the ports you want to use
for the trunk. For example, the following command sets ports C1 to C4 to LACP active:
switch(config) int c1-c4 lacp active
The preceding Example: works if the ports are not already operating in a trunk. To change the LACP option on
ports already operating as a trunk, you must first remove them from the trunk. For example, if ports C1 to C4 are
LACP-active and operating in a trunk with another device, you would do the following to change them to LACP-
passive:
switch(config)# no int c1-c4 lacp
Removes the ports from the trunk.
switch(config)# int c1-c4 lacp passive
Configures LACP passive.

Using keys to control dynamic LACP trunk configuration

The lacp key option provides the ability to control dynamic trunk configuration. Ports with the same key will be
aggregated as a single trunk.
There are two types of keys associated with each port, the Admin key and the Operational key. The Operational
key is the key currently in use. The Admin key is used internally to modify the value of the Operational key. The
130 Aruba 2930F / 2930M Management and Configuration Guide
for ArubaOS-Switch 16.08