Administrator Guide

19 Dell Campus Networking Interoperability with Cisco Catalyst 1.1 | version 1.1
U - in use N - not in use, no aggregation
f - failed to allocate aggregator
M - not in use, no aggregation due to minimum links not met
m - not in use, port not aggregated due to minimum links not met
u - unsuitable for bundling
d - default port
w - waiting to be aggregated
Number of channel-groups in use: 1
Number of aggregators: 1
Group Port-channel Protocol Ports
------+-------------+-----------+--------------------------------------------
13 Po13(SU) LACP Te2/3(P) Te2/4(P)
Last applied Hash Distribution Algorithm: Fixed
All configured port channels on the switch can be seen by using the show etherchannel summary
command.
2.5 LACP Standby
When LACP is configured, the protocol attempts to configure the maximum number of compatible ports in the
port channel, typically a maximum of eight ports per port channel. This default is generally the desired
behavior. It is possible, however, to configure a LACP enabled LAG to limit the number of active ports through
the use of the interface command, lacp max-bundle. Once the max bundles are set, participating links
can be given priority to determine active links and standby links. To do this, issue the interface command
lacp port-priority against the links participating in the port channel. A value from 1 to 65535 can be
used. Ports are assigned to the LAG in increasing numerical order from 1 to 65535 until the max-bundle value
is met, all ports after this value are set to a standby state.
When no priorities are defined for participating ports, an algorithm is used to automatically assign them. The
criteria used, in order of high to low, are LACP system priority, System ID (a combination of the LACP system
priority and the switch MAC address), LACP port priority and finally, the port number.
In Figure 8, two links are used for each port channel. The max-bundle command is set to 1 and the
participating links in the bundles are set to a lacp port-priority value of 1 and 65635. This results in one link
being active (solid line) and the other link being in a standby state (dashed line).