Administrator Guide

With this feature, you can create larger-capacity interfaces by utilizing a group of lower-speed links. For
example, you can build a 40-Gigabit interface by aggregating four 10-Gigabit Ethernet interfaces together. If
one of the five interfaces fails, traffic is redistributed across the three remaining interfaces.
Port Channel Implementation
The Dell Networking OS supports static and dynamic port channels.
• Static — Port channels that are statically configured.
• Dynamic — Port channels that are dynamically configured using the link aggregation control protocol
(LACP). For details, refer to Link Aggregation Control Protocol (LACP).
There are 128 port-channels with 16 members per channel.
As soon as you configure a port channel, the system treats it like a physical interface. For example, IEEE
802.1Q tagging is maintained while the physical interface is in the port channel.
Member ports of a LAG are added and programmed into the hardware in a predictable order based on the
port ID, instead of in the order in which the ports come up. With this implementation, load balancing yields
predictable results across line card resets and chassis reloads.
A physical interface can belong to only one port channel at a time.
Each port channel must contain interfaces of the same interface type/speed.
Port channels can contain a mix of 100, 1000, or 10000 Mbps Ethernet interfaces and TenGigabit Ethernet
interfaces. The interface speed (100, 1000, or 10000 Mbps) the port channel uses is determined by the first
port channel member that is physically up. The system disables the interfaces that do match the interface
speed that the first channel member sets. That first interface may be the first interface that is physically
brought up or was physically operating when interfaces were added to the port channel. For example, if the
first operational interface in the port channel is a Gigabit Ethernet interface, all interfaces at 1000 Mbps are
kept up, and all 100/1000/10000 interfaces that are not set to 1000 speed or auto negotiate are disabled.
100/1000/10000 Mbps Interfaces in Port
Channels
When both 100/1000/10000 interfaces and TenGigabitEthernet interfaces are added to a port channel, the
interfaces must share a common speed. When interfaces have a configured speed different from the port
channel speed, the software disables those interfaces.
The common speed is determined when the port channel is first enabled. At that time, the software checks
the first interface listed in the port channel configuration. If you enabled that interface, its speed configuration
becomes the common speed of the port channel. If the other interfaces configured in that port channel are
configured with a different speed, the system disables them.
For example, if four interfaces (TenGig 0/0, 0/1, 0/2, and 0/3) in which TenGig 0/0 and TenGig 0/3 are set to
speed 100 Mb/s and the others are set to 10000 Mb/s, with all interfaces enabled, and you add them to a port
channel by entering channel-member tengigabitethernet 0/0-3 while in port channel interface
mode, and the system determines if the first interface specified (TenGig 0/0) is up. After it is up, the common
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