Cisco BPX 8600 Series Switches

Serial Interface Unit Phase Errors (also known as CLKFAIL)

Document ID: 10803

Updated: Oct 02, 2006



Serial Interface Unit (SIU) phase errors are logged when the SIU is unable to properly receive an incoming cell. In particular, the SIU timed out while looking for the frame alignment pattern (FAP) in the serial data and gave up until the next frame cycle.



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What Do the Errors Mean?

An SIU always sends and receives, and sends Null BFrames when it has no other data available. When an SIU phase error occurs, either a Null BFrame or a Data Frame might have dropped, so traffic might be disrupted.

How Do I Make the Errors Go Away?

They are errors on the point-to-point data path, so they fit into the general category of debug.

Related Information

Updated: Oct 02, 2006
Document ID: 10803