Brocade Network OS Administrator’s Guide v4.1.1 - Manual (Page 447)

If a Brocade-based dynamic trunk is configured on a link and the link is not able to join the LAG, do the
following:
• Make sure that both ends of the link are configured as Brocade for trunk type.
• Make sure that both ends of the link are not configured for passive mode. They must be configured
as active /active, active /passive, or passive /active.
• Make sure that the port-channel interface is in the administrative "up" state by ensuring that the no
shutdown command was entered on the interface on both ends of the link.
• Make sure that the links that are part of the LAG are connected to the same neighboring switch.
• Make sure that the system ID of the switches connected by the link is unique. This can be verified by
entering the show lacp sys-id command on both switches.
• Make sure that LACPDUs are being received and transmitted on both ends of the link and there are
no error PDUs. This can be verified by entering the show lacp counters number command and
looking at the rx and tx statistics. The statistics should be incrementing and should not be at zero or a
fixed value. If the PDU rx count is not incrementing, check the interface for possible CRC errors by
entering the show interface link-name command on the neighboring switch.
• Make sure that the fiber length of the link has a deskew value of 7 microseconds. If it does not, the
link will not be able to join the LAG and the following RASLog message is generated: Deskew
calculation failed for link .
When a link has this problem, the show port-channel command displays the following message:
Mux machine state: Deskew not OK.
If a Brocade-based static trunk is configured on a link and the link is not able to join the LAG, do the
following:
• Make sure that both ends of the link are configured as Brocade for trunk type and verify that the
mode is "on."
• Make sure that the port-channel interface is in the administrative "up" state by ensuring that the no
shutdown command was entered on the interface on both ends of the link.
If a standards-based static trunk is configured on a link and the link is not able to join the LAG, do the
following:
• Make sure that both ends of the link are configured as standard for trunk type and verify that the
mode is "on."
• Make sure that the port-channel interface is in the administrative "up" state by ensuring that the no
shutdown command was entered on the interface on both ends of the link.
Configuring Link Aggregation
Network OS Administrator’s Guide 447
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