Connectivity Guide

Port-channel interfaces
Port-channels are not congured by default. Link aggregation (LA) is a method of grouping multiple physical interfaces into a single logical
interface — a link aggregation group (LAG) or port-channel. A port-channel aggregates the bandwidth of member links, provides
redundancy, and load balances trac. If a member port fails, the OS10 device redirects trac to the remaining ports.
A physical interface can belong to only one port-channel at a time. A port-channel must contain interfaces of the same interface type and
speed. OS10 supports a maximum of 128 port-channels, with up to thirty-two ports per channel.
To congure a port-channel, use the same conguration commands as the Ethernet port interfaces. Port-channels are transparent to
network congurations and manage as a single interface. For example, congure one IP address for the group, and use the IP address for
all routed trac on the port-channel.
By conguring port channels, you can create larger capacity interfaces by aggregating a group of lower-speed links. For example, you can
build a 40G interface by aggregating four 10G Ethernet interfaces together. If one of the four interfaces fails, trac redistributes across the
three remaining interfaces.
Static Port-channels are statically congured.
Dynamic Port-channels are dynamically congured using Link Aggregation Control Protocol (LACP).
Member ports of a LAG are added and programmed into the hardware based on the port ID, instead of the order the ports come up. Load
balancing yields predictable results across resets and reloads.
Create port-channel
You can create a maximum of 128 port-channels, with up to 32 port members per group. Congure a port-channel similarly to a physical
interface, enable or congure protocols, or ACLs to a port channel. After you enable the port-channel, place it in L2 or L3 mode.
To place the port-channel in L2 mode or congure an IP address to place the port-channel in L3 mode, use the switchport command.
• Create a port-channel in CONFIGURATION mode.
interface port-channel id-number
Create port-channel
OS10(config)# interface port-channel 10
Add port member
When you add an interface to a port-channel:
• The administrative status applies to the port-channel.
• The port-channel conguration is applied to the member interfaces.
• A port-channel operates in either L2 (default) or L3 mode. To place a port-channel in L2 mode, use the switchport mode
command. To place a port-channel in L3 mode and remove L2 conguration before you congure an IP address, use the no
switchport
command.
• All interfaces must have the same speed.
• An interface must not contain non-default L2/L3 conguration settings. Only the description and shutdown or no
shutdown
commands are supported. You cannot add an IP address or static MAC address to a member interface.
• You cannot enable ow control on a port-channel interface. Flow control is supported on physical interfaces that are port-channel
members.
• Port-channels support 802.3ad LACP. LACP identies similarly congured links and dynamically groups ports into a logical channel.
LACP activates the maximum number of compatible ports that the switch supports in a port-channel.
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Interfaces