Administrator Guide

Port channels can contain a mix of 10 or 40 Gigabit Ethernet interfaces. The interface speed (10, 40 Gbps) the port channel uses is
determined by the rst port channel member that is physically up. The system disables the interfaces that do match the interface speed
that the rst channel member sets. That rst interface may be the rst interface that is physically brought up or was physically operating
when interfaces were added to the port channel. For example, if the rst operational interface in the port channel is a 10–Gigabit Ethernet
interface, all interfaces at 40Gbps are kept up, and all 10/40 GbE interfaces that are not set to 10000 speed or auto negotiate are disabled.
The system brings up 10/40 GbE interfaces that are set to auto negotiate so that their speed is identical to the speed of the rst channel
member in the port channel.
10/40 Gbps Interfaces in Port Channels
When both 10/40 interfaces GigE interfaces are added to a port channel, the interfaces must share a common speed. When interfaces
have a congured speed dierent from the port channel speed, the software disables those interfaces.
The common speed is determined when the port channel is rst enabled. At that time, the software checks the rst interface listed in the
port channel conguration. If you enabled that interface, its speed conguration becomes the common speed of the port channel. If the
other interfaces congured in that port channel are congured with a dierent speed, the system disables them.
Conguration Tasks for Port Channel Interfaces
To congure a port channel (LAG), use the commands similar to those found in physical interfaces. By default, no port channels are
congured in the startup conguration.
These are the mandatory and optional conguration tasks:
• Creating a Port Channel (mandatory)
• Adding a Physical Interface to a Port Channel (mandatory)
• Reassigning an Interface to a New Port Channel (optional)
• Conguring the Minimum Oper Up Links in a Port Channel (optional)
• Adding or Removing a Port Channel from a VLAN (optional)
• Assigning an IP Address to a Port Channel (optional)
• Deleting or Disabling a Port Channel (optional)
• Load Balancing Through Port Channels (optional)
Creating a Port Channel
You can create up to 128 port channels with 16 port members per group on the switch.
To congure a port channel, use the following commands.
1 Create a port channel.
CONFIGURATION mode
interface port-channel id-number
2 Ensure that the port channel is active.
INTERFACE PORT-CHANNEL mode
no shutdown
After you enable the port channel, you can place it in Layer 2 or Layer 3 mode. To place the port channel in Layer 2 mode use the
switchport command, or congure and IP address to place the port channel in Layer 3 mode.
NOTE
: L3 is not supported on port extender (PE) ports or on port-channels when they have PE ports as members.
Interfaces 447