Fabric OS Reference Manual

170 Fabric OS Reference Manual
portLoopbackTest
Functional test of port N->N path.
Synopsis
portLoopbackTest [passCount]
Availability admin
Description Use this command to verify the functional operation of the switch by
sending frames from the port N transmitter, and looping the frames back
into the same port N receiver. The loopback is done at the parallel loopback
path. The path exercised in this test does not include the GBIC nor the fiber
cable.
Only one frame is transmitted and received at any one time. No external
cable is required to run this test. The port LEDs flicker green rapidly while
the test is running.
The test method consists of these steps:
1. Set all ports for parallel loopback.
2. Create a frame F of maximum data size (2112 bytes).
3. Transmit frame F through port N.
4. Pick up the frame from the same port N.
5. Check the eight statistic error counters for nonzero values:
ENC_in, CRC_err, TruncFrm, FrmTooLong, BadEOF,
Enc_out, BadOrdSet, DiscC3
6. Check if the transmit, receive, or class 3 receiver counters are stuck at
some value.
7. Check if the number of frames transmitted is not equal to the number of
frames received.
8. Repeat steps 2 through 7 for all ports present until these results occur:
– The number of frames (or
passCount
) requested is reached.
– All ports are marked bad.