Learn some of these steps from Mellanox Academy Online Training

Step 1: Clear all counters and begin the test execution

ibdiagnet -pc

Wait for a while. Usually, it may take 30 to 60 mins

Check for errors that exceed the allowed threshold

ibdiagnet -ls 25 -lw 4x -P all=1 --pm_pause_time 30

• Specify the link speed
  -ls <2.5|5|10|14|25|50> 
• Specify the Link width
  -lw <1x|4x|8x|12x>
• Check Information provide from all counters and display each one of them crossing threshold of 1
  -P all=1
• The time between the two samples is set by the –pm_pause_time option