35
•
Unselected: An Unselected port cannot forward user traffic.
Operational key
When aggregating ports, the system automatically assigns each port an operational key based on port
information such as port rate and duplex mode. Any change to this information triggers a recalculation
of the operational key.
In an aggregation group, all selected member ports are assigned the same operational key.
Configuration classes
Every configuration setting on a port might affect its aggregation state. Port configurations fall into the
following classes:
•
Port attribute configurations
—
Includes port rate, duplex mode, and link status (up/down). These
are the most basic port configurations.
•
Class-two configurations
—
A member port can be placed in Selected state only if it has the same
class-two configurations as the aggregate interface. Class-two configurations made on an
aggregate interface are automatically synchronized to all its member ports. These configurations
are retained on the member ports even after the aggregate interface is removed.
Table 2
Class-two configurations
Feature
Considerations
Port isolation
Whether the port has joined an isolation group
QinQ
QinQ enable state (enable/disable), TPID for VLAN tags, outer VLAN tags to be
added, inner-to-outer VLAN priority mappings, inner-to-outer VLAN tag
mappings, inner VLAN ID substitution mappings
VLAN
Permitted VLANs, PVID, link type (trunk, hybrid, or access), IP subnet-based VLAN
configuration, protocol-based VLAN configuration, VLAN tagging mode
MAC address learning
MAC address learning capability
NOTE:
Any class-two configuration change might affect the aggregation state of link aggregation member ports
and ongoing traffic. To be sure that you are aware of the risk, the system displays a warning message
every time you attempt to change a class-two configuration setting on a member port.
•
Class-one configurations
—Include settings that do not affect the aggregation state of the member
port even if they are different from those on the aggregate interface. GVRP and MSTP settings are
examples of class-one configurations. The class-one configuration for a member port is effective
only when the member port leaves the aggregation group.
Reference port
When setting the aggregation state of the ports in an aggregation group, the system automatically picks
a member port as the reference port. A Selected port must have the same port attributes and class-two
configurations as the reference port.
LACP
The IEEE 802.3ad Link Aggregation Control Protocol (LACP) enables dynamic aggregation of physical
links. It uses link aggregation control protocol data units (LACPDUs) for exchanging aggregation
information between LACP-enabled devices.
1.
LACP functions
