604 | Link Aggregation Control Protocol (LACP)w w w . d e l l . c o m | s u p p o r t . d e l l . c o m Important Points to Remember• LACP enables you to add members to a port channel (LAG) as long as it has no static members.Conversely, if the LAG already contains a statically defined member (channel-member command),the port-channel mode command is not permitted.• A static LAG cannot be created if a dynamic LAG using the selected number already exists.• No dual membership in static and dynamic LAGs:• If a physical interface is a part of a static LAG, then the command port-channel-protocol lacpwill be rejected on that interface.• If a physical interface is a part of a dynamic LAG, it cannot be added as a member of a static LAG.The command channel-member gigabitethernet x/y will be rejected in the static LAG interfacefor that physical interface.• A dynamic LAG can be created with any type of configuration.• There is a difference between the shutdown and no interface port-channel:• The shutdown command on LAG “xyz” disables the LAG and retains the user commands.However, the system does not allow the channel number “xyz” to be statically created.• The command no interface port-channel channel-number deletes the specified LAG, including adynamically created LAG. This command causes all LACP-specific commands on the memberinterfaces to be removed. The interfaces are restored to a state that is ready to be configured.Note: There will be no configuration on the interface since that condition is required for aninterface to be part of a LAG.• Link dampening can be configured on individual members of a LAG. See Link Debounce Timer formore information.LACP modesFTOS provides the following three modes for configuration of LACP:• Off—In this state, an interface is not capable of being part of a dynamic LAG. LACP does not run onany port that is configured to be in this state.• Active—In this state, the interface is said to be in the “active negotiating state.” LACP runs on anylink that is configured to be in this state. A port in Active state also automatically initiates negotiationswith other ports by initiating LACP packets.• Passive—In this state, the interface is not in an active negotiating state, but LACP will run on the link.A port in Passive state also responds to negotiation requests (from ports in Active state). Ports inPassive state respond to LACP packets.FTOS supports LAGs in the following cases:• A port in Active state can set up a port channel (LAG) with another port in Active state.• A port in Active state can set up a LAG with another port in Passive state.A port in Passive state cannot set up a LAG with another port in Passive state.
