Administrator Guide
Port Channel Interfaces
Port channel interfaces support link aggregation, as described in IEEE Standard 802.3ad.
This section covers the following topics:
• Port Channel Denition and Standards
• Port Channel Benets
• Port Channel Implementation
• Conguration Tasks for Port Channel Interfaces
Port Channel Denition and Standards
Link aggregation is dened by IEEE 802.3ad as a method of grouping multiple physical interfaces into a single logical interface—a link
aggregation group (LAG) or port channel.
A LAG is “a group of links that appear to a MAC client as if they were a single link” according to IEEE 802.3ad. In Dell Networking OS, a
LAG is referred to as a port channel interface.
A port channel provides redundancy by aggregating physical interfaces into one logical interface. If one physical interface goes down in the
port channel, another physical interface carries the trac.
Port Channel Benets
A port channel interface provides many benets, including easy management, link redundancy, and sharing.
Port channels are transparent to network congurations and can be modied and managed as one interface. For example, you congure
one IP address for the group and that IP address is used for all routed trac on the port channel.
With this feature, you can create larger-capacity interfaces by utilizing a group of lower-speed links. For example, you can build a 5-Gigabit
interface by aggregating ve 1-Gigabit Ethernet interfaces together. If one of the ve interfaces fails, trac is redistributed across the
remaining interfaces.
Port Channel Implementation
Dell Networking OS supports static and dynamic port channels.
• Static — Port channels that are statically congured.
• Dynamic — Port channels that are dynamically congured using the link aggregation control protocol (LACP). For details, see Link
Aggregation Control Protocol (LACP).
There are 128 port-channels with 16 members per channel.
As soon as you congure a port channel, Dell Networking OS 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 device 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 1G/10G/40G. The interface speed that the port channel uses is determined by the rst port channel
member that is physically up. Dell Networking OS disables the interfaces that do not match the interface speed that the rst channel
Interfaces
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