Chapter 3: Configuration Guide
Configuring Link Aggregation (LAG)
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Configuring Link Aggregation (LAG)
Link aggregation (LAG) enables you to group several physical Ethernet or radio interfaces into a
single logical interface bound to a single MAC address. This logical interface is known as a LAG
group. Traffic sent to the interfaces in a LAG group is distributed by means of a load balancing
function. PTP 820 uses a distribution function of up to Layer 4 in order to generate the most
efficient distribution among the LAG physical ports.
This section explains how to configure LAG and includes the following topics:
LAG Overview
LAG can be used to provide redundancy for Ethernet interfaces, both on the same PTP 820 unit
(line protection) and on separate units (line protection and equipment protection). LAGs can also
be used to provide redundancy for radio links.
LAG can also be used to aggregate several interfaces in order to create a wider (aggregate) link.
For example, LAG can be used to create a 4 Gbps channel.
You can create up to four LAG groups. The following restrictions exist with respect to LAG groups:
Only physical interfaces (including radio interfaces), not logical interfaces, can belong to a LAG
group.
Interfaces can only be added to the LAG group if no services or service points are attached to
the interface.
Any classification rules defined for the interface are overridden by the classification rules
defined for the LAG group.
When removing an interface from a LAG group, the removed interface is assigned the default
interface values.
There are no restrictions on the number of interfaces that can be included in a LAG. It is
recommended, but not required, that each interface in the LAG have the same parameters (e.g.,
speed, duplex mode).
The LAG page lists all LAG groups configured on the unit.
Note
To add or remove an Ethernet interface to a LAG group, the interface must be in an
administrative state of “down”. This restriction does not apply to radio interfaces. For
instructions on setting the administrative state of an interface, see
Interfaces (Interface Manager)