Configuring The Lacp System Priority; Configuring The Lacp Port Priority - Cisco IE-3000-8TC Software Configuration Manual

Configuring EtherChannels
In priority comparisons, numerically lower values have higher priority. The priority decides which ports
should be put in standby mode when there is a hardware limitation that prevents all compatible ports
from aggregating.
Determining which ports are active and which are hot standby is a two-step procedure. First the system
with a numerically lower system priority and system-id is placed in charge of the decision. Next, that
system decides which ports are active and which are hot standby, based on its values for port priority
and port number. The port-priority and port-number values for the other system are not used.
You can change the default values of the LACP system priority and the LACP port priority to affect how
the software selects active and standby links. For more information, see the
System Priority" section on page 38-16
page

Configuring the LACP System Priority

You can configure the system priority for all the EtherChannels that are enabled for LACP by using the
lacp system-priority global configuration command. You cannot configure a system priority for each
LACP-configured channel. By changing this value from the default, you can affect how the software
selects active and standby links.
You can use the show etherchannel summary privileged EXEC command to see which ports are in the
hot-standby mode (denoted with an H port-state flag).
Beginning in privileged EXEC mode, follow these steps to configure the LACP system priority. This
procedure is optional.
Command
Step 1 configure terminal
Step 2
lacp system-priority priority
Step 3 end
Step 4 show running-config
or
show lacp sys-id
Step 5
copy running-config startup-config
To return the LACP system priority to the default value, use the no lacp system-priority global
configuration command.

Configuring the LACP Port Priority

By default, all ports use the same port priority. If the local system has a lower value for the system
priority and the system ID than the remote system, you can affect which of the hot-standby links become
active first by changing the port priority of LACP EtherChannel ports to a lower value than the default.
The hot-standby ports that have lower port numbers become active in the channel first. You can use the
show etherchannel summary privileged EXEC command to see which ports are in the hot-standby
mode (denoted with an H port-state flag).
Cisco IE 3000 Switch Software Configuration Guide
38-16
38-16.
Chapter 38 Configuring EtherChannels and Link-State Tracking
and the "Configuring the LACP Port Priority" section on
Purpose
Enter global configuration mode.
Configure the LACP system priority.
For priority, the range is 1 to 65535. The default is 32768.
The lower the value, the higher the system priority.
Return to privileged EXEC mode.
Verify your entries.
(Optional) Save your entries in the configuration file.
"Configuring the LACP
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