If the adapter argument is missing, all Fibre Channel adapters and disks in the system are tested, otherwise only the specified adapter, and disks attached to it, are tested.
When finished, fctest prints out a report of the following values for each Fibre Channel adapter tested:
1. Number of times loss of synchronization was detected in that adapter's Fibre Channel loop.
2. Number of CRC errors found in Fibre Channel packets.
3. The total number of inbound and outbound frames seen by the adapter.
4. A "confidence factor" on a scale from 0 to 1 that indicates the health of your Fibre Channel system as computed by the test. A value of 1 indicates that no significant errors were found. Any value less than 1 indicates there are problems in the Fibre Channel loop that are likely to intefere with the normal operation of your appliance. There is a troubleshooting checklist for Fibre Channel problems in your System Administrator's Guide that may help indentify and correct the problem.
If the confidence factor is reported as less than 1, please go through the troubleshooting checklist for Fibre Channel loop problems in the System Administrator's Guide and re-run the fctest command after making any suggested modifications to your Fibre Channel setup.
The actual arithmetic that is used to compute the confidence factor is as follows:
The number of Fibre Channel frame errors is obtained by adding the number of CRC and Synchronization errors, with each sync error weighted ten times as much as a CRC error. The number of errors is then divided by the total number of Fibre Channel frames (inbound + outbound). The quotient is subtracted from 1 to get the final answer.
C = 1 - (Crc + 10Sync)/F,
where C = the confidence factor, representing the integrity of your FC system.
Crc = number of CRC errors observed in the Fibre Channel frames.
Sync = number of Fibre Channel synchronization errors.
F = the total number of inbound and outbound frames seen by the adapter.