[Beowulf] InfiniBand VL15 error

[Prentice Bisbal]

I'm getting this error when I run ibchecknet on my cluster:

#warn: counter VL15Dropped = 476        (threshold 100) lid 1 port 1
Error check on lid 1 (aurora HCA-1) port 1:  FAILED

I've googled around this morning, but haven't found anything helpful.
Most of the hits turn up code with the phrase "VL15Dropped", but nothing
explaining what this error means, what causes it, or how to fix it.

After clearing the counters with 'perfquery -r', the VL15Dropped count
starts increasing from zero almost immediately.

Any ideas what this error represents or how to fix? Could it be a bad
cable?

--
Prentice