Enterasys Networks Enterasys D2 D2G124-12P - Manual (Page 139)

Link Aggregation Control Protocol (LACP)
D-Series CLI Reference 4-35
D-Series Usage Considerations
In normal usage (and typical implementations) there is no need to modify any of the default
LACP parameters on the switch. The default values will result in the maximum number of
aggregations possible. If the switch is placed in a configuration with its peers not running the
protocol, no dynamic link aggregations will be formed and the switch will function normally (that
is, will block redundant paths). For information about building static aggregations, refer to set
lacp static (
page 4‐40 ).
Each D‐Series module provides six virtual link aggregator ports, which are designated in the CLI
as lag.0.1 through lag.0.6. Each LAG can have up to associated physical ports. Once underlying
physical ports (for example,
ge .x.x, or ge .x.x) are associated with an aggregator port, the resulting
aggregation will be represented as one LAG with a lag.x.x port designation. LACP determines
which underlying physical ports are capable of aggregating by comparing operational keys.
Aggregator ports allow only underlying ports with keys matching theirs to join their LAG.
LACP uses a system priority value to build a LAG ID, which determines aggregation precedence.
If there are two partner devices competing for the same aggregator, LACP compares the LAG IDs
for each grouping of ports. The LAG with the lower LAG ID is given precedence and will be
allowed to use the aggregator.
Table 4-15 LACP Terms and Definitions
Term Definition
Aggregator Virtual port that controls link aggregation for underlying physical ports. Each
D-Series module provides 6 aggregator ports, which are designated in the
CLI as lag.0.1 through lag.0.6.
LAG Link Aggregation Group. Once underlying physical ports (for example, ge.x.x)
are associated with an aggregator port, the resulting aggregation will be
represented as one LAG with a lag.x.x port designation.
D-Series LAGs can have up to associated physical ports.
LACPDU Link Aggregation Control Protocol Data Unit. The protocol exchanges
aggregation state/mode information by way of a port’s actor and partner
operational states. LACPDUs sent by the first party (the actor) convey to the
second party (the actor’s protocol partner) what the actor knows, both about
its own state and that of its partner.
Actor and Partner An actor is the local device sending LACPDUs. Its protocol partner is the
device on the other end of the link aggregation. Each maintains current status
of the other via LACPDUs containing information about their ports’ LACP
status and operational state.
Admin Key Value assigned to aggregator ports and physical ports that are candidates for
joining a LAG. The LACP implementation on D-Series devices will use this
value to form an oper key and will determine which underlying physical ports
are capable of aggregating by comparing oper keys. Aggregator ports allow
only underlying ports with oper keys matching theirs to join their LAG. On D-
Series devices, the default admin key value is 32768.
System Priority Value used to build a LAG ID, which determines aggregation precedence. If
there are two partner devices competing for the same aggregator, LACP
compares the LAG IDs for each grouping of ports. The LAG with the lower
LAG ID is given precedence and will be allowed to use the aggregator.
Note: Only one LACP system priority can be set on a D-Series
device, using either the set lacp asyspri command (
page 4-38 ),
or the set port lacp command ( page 4-44 ).