ignore /dev/md folder

tests/test_raid.py

@@ -30,7 +30,9 @@ def check_raid(dev):
 if os.path.isfile('/proc/mdstat'):
     all_ok = True
     for r in glob.glob('/dev/md*'):
-        all_ok = min(check_raid(r), all_ok)
+        # ignore /dev/md folder
+        if os.path.isfile(r):
+            all_ok = min(check_raid(r), all_ok)
     if all_ok:
         print_green('Everything fine')
     else: