HP StorageWorks MSA 2/8 HP StorageWorks Fabric OS V3.1.x/4.1.x Reference Guide - Page 587

portLoopbackTest portLoopbackTest Functional test of port N->N path. Synopsis: V3.1.x portLoopbackTest [passCount] Synopsis: V4.1.x portLoopbackTest [--slot number][-nframes count] [-lb_mode mode][-spd_mode mode][-ports itemlist] Availability Admin Release V3.1.x and V4.1.x 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 media, SFP, 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. Below is the test method: 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 8 statistic error counters for nonzero values: ENC_in, CRC_err, TruncFrm, FrmTooLong, BadEOF, Enc_out, BadOrdSet, DiscC3 Fabric OS Version 3.1.x/4.1.x Reference Guide 587