Technical data

26 Brocade 6910 Ethernet Access Switch Diagnostic Guide
53-1002348-02
LACP trunking
Admin State: defaulted, distributing, collecting,
synchronization, long timeout,
Oper State: distributing, collecting, synchronization,
aggregation, long timeout, LACP-activity
.
.
.
Configuration notes
• You cannot use 802.3ad link aggregation on a port configured as a member of a static trunk
group.
• When LACP dynamically adds or changes a trunk group, the show interface status port-channel
command displays the trunk as both configured and active. However, the show running-config
commands do not contain a trunk command defining the new or changed trunk group.
• You can enable link aggregation on 802.1q tagged ports that belong to more than one
port-based VLAN.
• Brocade recommends that you disable or remove the cables from the ports you plan to enable
for dynamic link aggregation. Doing so prevents the possibility that LACP will use a partial
configuration to talk to the other side of a link. A partial configuration does not cause errors,
but sometimes requires LACP to be disabled and re-enabled on both sides of the link to ensure
that a full configuration is used. It is easier to disable a port or remove its cable first. This
applies both for active link aggregation and passive link aggregation.
Trunk formation rules
When troubleshooting trunks, make sure the following rules for trunk formation have been
considered:
• Any number of ports between 2 and 12 within the same chassis can be used to configure a
trunk port.
• Ports in a trunk must have the same speed, negotiation mode, and Quality of Service (QoS)
priority or the trunk is rejected.
• All ports configured in a trunk must be configured with the same port attributes.
• Primary port policy applies to all secondary ports. No trunk is rejected.
• The trunk is rejected if any trunk port has mirroring or monitoring configured.
• The trunk is rejected if any trunk port has VLAN or inner-VLAN translation configured (also
known as VLAN trunking).
Common diagnostic scenarios
• LACP trunk links may not operate properly between Brocade devices and third-party devices
because of a mismatch between the link configurations. If the link is fixed on the third-party
side, the link on the Brocade side must be a trunk. If it is link-aggregated on the third-party
side, then it must be the same on the Brocade side.
• LACP links may not operate properly due to misconfigurations. Contact Brocade Technical
Support for help with configuration issues.