Link Aggregation Overview
Fixed Switch Configuration Guide 11-7
Single Port Attached State Rules
By default, a LAG must contain two or more actor and partner port pairs for the LAG to be
initiated by this device. A feature exists to allow the creation of a single port LAG that is disabled
by default. If single port LAG is enabled, a single port LAG can be created on this device. If single
port LAG is disabled, a single port LAG will not be initiated by this device. If a peer device is able
to form a single port LAG and advertises its willingness to do so, a single port LAG can form.
There are three conditions under which a single port LAG can exist and the LAG member can be
moved to the attached state:
• The single port LAG feature is enabled.
or,
• The single port LAG feature is disabled, but the peer device is able and willing to form a single
port LAG.
or,
• An already existing LAG configuration persists through a device or module reset. If upon
reset there is only a single port active for an already existing LAG, that single port will move
to the attached state regardless of the single port LAG setting.
LAG Port Parameters
LAG port parameters can be changed per port.
Table 11-2 specifies the LACP port parameters that can be changed.
Table 11-2 LAG Port Parameters
Term Definition
Port Admin Key The port admin key can be set for both the actor and partner side of the link. The
admin key only affects the local device. LACP uses this value to determine which
underlying physical ports are capable of aggregating. Aggregator ports allow only
underlying ports with physical port and LAG admin keys that match to join a LAG.
Setting the physical port admin key to a different value than any LAG resource on the
device will ensure that this link does not join a LAG. Valid values are 1 - 65535.
Default value is 32768.
Port Priority Port priority can be set for both the actor and partner side of the link. The port priority
plays a role in determining which set of ports will move to the attached state and
pass traffic. The lower port priority, for the port on the system in charge of selecting
ports to move to the attached state, determines which ports will actually move to the
attached state. If a LAG is made up of ports with different speeds, setting a lower port
priority to ports with the desired speed for the LAG will ensure that those ports move
to the attached state. Port priority is also used to determine which ports join a LAG if
the number of ports available exceeds the number of ports supported for that device.
Valid values are 0 - 65535, with lower values designating higher priority. Default
value is 32768.
To Next Page
Loading...
Need help?
General