If the -v option is specified, the output is verbose.
If the -B option is specified, disks attached to the Fibre Channel loop via their B ports will also be tested.
By default, the test runs for about 5 minutes. However, if the [ -t minutes ] are given, the test will run for the specified duration.
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. The argument specifies the PCI slot number of the adapter.
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. For more information see the Easy Installation Instructions for your specific filer or your Fibre Channel Storage Shelf Guide.
If the confidence factor is reported as less than 1, please go through the troubleshooting checklist for Fibre Channel loop problems in the document "Easy Installation Instructions for Netapp Filers" and re-run the fctest command after making any suggested modifications to your Fibre Channel setup. If the problem persists, please call your Customer Support telephone number.
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.
The following command runs fctest for 5 minutes in verbose mode on all Fibre Channel adapters in the system, while testing only those disks which are attached via their A ports:
fctest -v -B
The following command runs fctest for an hour in verbose mode, while testing disks attached to adapter 8 via both A and B ports:
fctest -v -B -t 60 8