Running The Loopback Test; Running The Read/Write Buffer Test - Qlogic SANsurfer FC HBA Manager User Manual

8 – Performing Diagnostics
Running Loopback and Read/Write Buffer Diagnostic Tests

Running the Loopback Test

The loopback test is external to the HBA. If the HBA port is in loop mode, you can
run the loopback test with a loopback connector. If the HBA port is in point-to-point
mode and attached to a switch, an echo test is run instead (no loopback
connector is used). In addition, some driver versions do not require a loopback
connector. See
The test evaluates the ports (transmit and receive transceivers) on the HBA. More
specifically, the loopback test transmits and receives (loopback) the specified
data, performs a frame cyclic redundancy check (CRC), and looks for disparity
and length errors.
To run a loopback test:
1. Prepare for the test (see
2. Set the diagnostic test parameters (see
Parameters
3. Run the diagnostic test (see
4. View the diagnostic test results (see
the help system).
5. Prepare for normal HBA operations (see
Operations" on page
NOTE:
The loopback test must be run with the loopback connector (unless the
operating system uses one of the driver versions listed in the
NOTE:
The loopback test is disabled if you are using inbox drivers with SLES 10.0.

Running the Read/Write Buffer Test

The read/write buffer test sends specified data through the SCSI Write Buffer
command to a target device (disk or tape). It then reads the data back through the
SCSI Read Buffer command and compares the data for errors. The test also
compares the link status of the device before and after the read/write buffer test. If
errors occur, the test indicates a broken or unreliable link between the HBA port
and the device.
NOTE:
Link status is disabled if you are using inbox drivers with SLES 10.0.
8-6
"Preparing for the Loopback Test" on page 8-3
"Preparing for Diagnostic Testing" on page
in the help system).
Running Diagnostic Tests
8-4).
for information.
Setting the Diagnostic Test
in the help system).
Viewing the Diagnostic Test Results
"Preparing for Normal HBA
S
8-2).
in
Table 8-1.
SN0054651-00 B