Subinterfaces let you divide a physical, redundant, or EtherChannel interface into multiple logical
interfaces that are tagged with different VLAN IDs. An interface with one or more VLAN subinterfaces
is automatically configured as an 802.1Q trunk. Because VLANs allow you to keep traffic separate on a
given physical interface, you can increase the number of interfaces available to your network without
adding additional physical interfaces or ASAs. This feature is particularly useful in multiple context
mode so that you can assign unique interfaces to each context.

Step 4

port-channel load-balance

{dst-ip |

dst-ip-port

| dst-mac | dst-port |

src-dst-ip

| src-dst-ip-port | src-dst-mac

| src-dst-port | src-ip | src-ip-port |

src-mac

| src-port | vlan-dst-ip |

vlan-dst-ip-port

| vlan-only |

vlan-src-dst-ip

| vlan-src-dst-ip-port |

vlan-src-ip

| vlan-src-ip-port}

Example:

hostname(config-if)# port-channel

load-balance src-dst-mac

Configures the load-balancing algorithm. By default, the ASA
balances the packet load on interfaces according to the source and
destination IP address (src-dst-ip) of the packet. If you want to
change the properties on which the packet is categorized, use this
command. For example, if your traffic is biased heavily towards
the same source and destination IP addresses, then the traffic
assignment to interfaces in the EtherChannel will be unbalanced.
Changing to a different algorithm can result in more evenly
distributed traffic. For more information about load balancing, see
the

“Load Balancing” section on page 6-7

Step 5

lacp system-priority

number

Example:

hostname(config)# lacp system-priority

12345

Sets the LACP system priority, from 1 to 65535. The default is
32768. The higher the number, the lower the priority. This
command is global for the ASA.

If the device at the other end of the EtherChannel has conflicting
port priorities, the system priority is used to determine which port
priorities to use. For interface priorities within an EtherChannel,
see the lacp port-priority command in the

“Adding Interfaces to

the EtherChannel” section on page 6-27

Step 6

(Optional)

You can set the Ethernet properties for the
port-channel interface to override the properties
set on the individual interfaces.

This method provides a shortcut to set these parameters because
these parameters must match for all interfaces in the channel
group. See the

“Enabling the Physical Interface and Configuring

Ethernet Parameters” section on page 6-22

for Ethernet

commands.

Command

Purpose