Issue

-With RHEL 5 you have the following sysfs directory.

root # ls /sys/class/infiniband/mlx4_0/diag_counters/
clear_diag  num_eqovf     rq_num_lle    rq_num_mce  rq_num_rire   rq_num_ucsdprd  sq_num_bre     sq_num_leeoe  sq_num_lqpoe  sq_num_rabrte  sq_num_rnr   sq_num_rsync
num_baddb   rq_num_lae    rq_num_lpe    rq_num_oos  rq_num_rnr    rq_num_udsdprd  sq_num_ieecne  sq_num_lle    sq_num_mwbe   sq_num_rae     sq_num_roe   sq_num_tree
num_cqovf   rq_num_leeoe  rq_num_lqpoe  rq_num_rae  rq_num_rsync  rq_num_wrfe     sq_num_ieecse  sq_num_lpe    sq_num_oos    sq_num_rire    sq_num_rree  sq_num_wrfe

• However with RHEL 6 it was removed.

root # ls /sys/class/infiniband/mlx4_0/diag_counters/
ls: cannot access /sys/class/infiniband/mlx4_0/diag_counters/: No such file or directory

• These counters give us some more in depth information about what the HCA is doing.
• Their absence make troubleshooting more difficult.