director product manager user guide
2–39
Monitoring and Managing the Director
Error Statistics
Port errors indicate that a port is not operating correctly. Use this data to isolate
problems with port and link operations. The statistics in this table include:
•
Link failures—A link failure was recorded in response to a not operational
sequence (NOS), protocol timeout, or port failure. At the Port Card View, a
yellow triangle displays to indicate a link incident, or a blinking red and yellow
diamond displays to indicate a port failure.
•
Sync losses—A loss of synchronization was detected because the attached device
was reset or disconnected from the port. At the Port Card View, a yellow triangle
displays to indicate a link incident.
•
Signal losses—A loss of signal was detected because the attached device was
reset or disconnected from the port. At the Port Card View, a yellow triangle
displays to indicate a link incident.
•
Primitive sequence errors—An incorrect primitive sequence was received from
the attached device, indicating a Fibre Channel link-level protocol violation. At
the Port Card View, a yellow triangle displays to indicate a link incident.
•
Discarded frames—A received frame could not be routed and was discarded
because the frame timed out (insufficient buffer-to-buffer credit) or the destination
device was not logged into the director.
•
Invalid transmission words—The number of times that the director detected
invalid transmission words from the attached device. This indicates that a frame or
primitive sequence arrived at the director’s port corrupted. This corruption can be
due to the attached device performing a reset, plugging or unplugging the link,
bad optics at either end of the cable, bad cable, or a dirty or poor connection.
Moving the connection around or replacing cables can isolate the problem.
Some number of invalid transmission words are expected and acceptable. Invalid
transmission words within a frame are used to produce the bit-error threshold link
incident. If one or more invalid transmission words are detected in 12 separate
1.5-second samples within five minutes, a bit-error threshold link incident is
generated.
•
CRC errors—A received frame failed a cyclic redundancy check (CRC)
validation, indicating the frame arrived at the director’s port corrupted. Frame
corruption may be caused by device disconnection, an optical transceiver failure at
the device, a bad fiber-optic cable, or a poor cable connection.
