68NOTE:• The router supports up to 240 aggregation groups.• On a Layer 3 aggregate interface, you can create subinterfaces. These subinterfaces are logicalinterfaces that operate at the network layer. They can receive VLAN tagged packets for their Layer 3aggregate interface.• The rate of an aggregate interface equals the total rate of its member ports in Selected state, and itsduplex mode is the same as the selected member ports. For more information about the states ofmember ports in an aggregation group, see “Aggregation states of member ports in an aggregationgroup.”Aggregation states of member ports in an aggregation groupA member port in an aggregation group can be in either of the following aggregation states:• Selected—A Selected port can forward user traffic.• Unselected—An Unselected port cannot forward user traffic.Operational keyWhen aggregating ports, the system automatically assigns each port an operational key based on portinformation such as port rate and duplex mode. Any change to this information triggers a recalculationof the operational key.In an aggregation group, all selected member ports are assigned the same operational key.Configuration classesEvery configuration setting on a port may affect its aggregation state. Port configurations fall into thefollowing classes:• Port attribute configurations, including port rate, duplex mode, and link status (up/down), whichare the most basic port configurations.• Class-two configurations, as described in Table 8. A member port can be placed in Selected stateonly if it has the same class-two configurations as the aggregate interface.Table 8 Class-two configurationsFeature ConsiderationsPort isolation Whether the port has joined an isolation group, and the isolation group to whichthe port belongsQinQQinQ enable state (enable/disable), TPID for VLAN tags, outer VLAN tags to beadded, inner-to-outer VLAN priority mappings, inner-to-outer VLAN tagmappings, inner VLAN ID substitution mappingsVLAN Permitted VLAN IDs, PVID, link type (trunk, hybrid, or access), IP subnet-basedVLAN configuration, protocol-based VLAN configuration, VLAN tagging modeMAC address learningMAC address learning capability, MAC address learning limit, forwarding offrames with unknown destination MAC addresses after the MAC addresslearning limit is reached
