Comment 2 for bug 1989894

setting this to medium as i do not belive disabling debug logging will avoid this.

looking at os-brick device_path will be set in some fiber channel backend but its not always set so
we should not depend on it in our log message without at least checking if its set.

so this is valid but this is also not a common deployment configuration so the expected impact on user of nova is small.
for those that re hit by this however its a problem that should be fixed.