User manual

2
Performance View
2-35
Monitoring and Managing the Switch
• Signal losses
A loss of signal was detected because the attached device was
reset or disconnected from the port. At the Hardware View, a
yellow triangle appears 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 Hardware View, a yellow triangle appears 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 switch.
• Invalid transmission words
The number of times that the switch detected invalid
transmission words from the attached device. This indicates that
a frame or primitive sequence arrived at the switch’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 switch’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.