Administrator Guide

Layer 2 Switching Commands 651
console(config)#interface gigabitethernet 1/0/8
console(config-if-Gi1/0/8)#lacp port-priority 247
lacp system-priority
Use the lacp system-priority command in Global Configuration mode to
configure the Link Aggregation system priority. To reset to default, use the no
form of this command.
Syntax
lacp system-priority value
no lacp system-priority
• value — Port priority value. (Range: 1–65535)
Default Configuration
The default system priority value is 1.
Command Mode
Global Configuration mode
User Guidelines
Per IEEE 802.1AX-2008 Section 5.6, ports are selected for aggregation by each
switch based upon the port priority assigned by the switch with the higher
system priority, starting with the highest priority port of the switch with the
higher switch priority, and working downward through the ordered list of port
priority values for the ports.
The system priority of each switch is an eight octet binary number, formed by
using the configured system priority as the two most significant octets and
the switch id (MAC address) as the least significant six octets. For a given
switch and link aggregation partner, the switch with the numerically lower
value of system priority has the higher priority.
The selection algorithm is reapplied upon changes in the membership of the
port channel (for example, if a link fails, or if a new link joins the group) and
any subsequent changes to the set of active links are made according to the
above algorithm.
2CSNXXX_SWUM204.book Page 651 Monday, January 25, 2016 1:25 PM