Configuration Guide User guide

726 FastIron Configuration Guide
53-1002494-02
Dynamic link aggregation
System priority
The system priority parameter specifies the link aggregation priority on the Brocade device relative
to the devices at the other ends of the links on which link aggregation is enabled. A higher value
indicates a lower priority. You can specify a priority from 0 through 65535. The default is 1.
NOTE
If you are connecting the Brocade device to another vendor device and the link aggregation feature
is not working, set the system priority on the Brocade device to a lower priority (a higher priority
value). In some cases, this change allows the link aggregation feature to operate successfully
between the two devices.
Port priority
The port priority parameter determines the active and standby links. When a group of ports is
negotiating with a group of ports on another device to establish a trunk group, the Brocade port
with the highest priority becomes the default active port. The other ports (with lower priorities)
become standby ports in the trunk group. You can specify a priority from 0 through 65535. A higher
value indicates a lower priority. The default is 1.
NOTE
The primary port in the port group becomes the default active port. The primary port is the
lowest-numbered port in a valid trunk port group.
Timeout
You can specify a timeout mode, which determines how fast ports are removed from a trunk. Refer
to “Configuring link aggregation parameters” on page 729 for more information.
Key
Every port that is link aggregation-enabled has a key. The key identifies the group of potential trunk
ports to which the port belongs. Ports with the same key are called a key group and are eligible to
be in the same trunk group.
When you enable link aggregation on an untagged port, the software assigns a default key to the
port. For tagged ports, you must manually configure link aggregation keys. Refer to “Configuring
keys for ports with link aggregation enabled” on page 729.
All ports within an aggregate link must have the same key. However, if the device has ports that are
connected to two different devices, and the port groups allow the ports to form into separate
aggregate links with the two devices, then each group of ports can have the same key while
belonging to separate aggregate links with different devices. Figure 69 on page 727 shows an
example.