Documentation/device-mapper/dm-flakey.txt

   1 dm-flakey
   2 =========
   3
   4 This target is the same as the linear target except that it returns I/O
   5 errors periodically.  It's been found useful in simulating failing
   6 devices for testing purposes.
   7
   8 Starting from the time the table is loaded, the device is available for
   9 <up interval> seconds, then returns errors for <down interval> seconds,
  10 and then this cycle repeats.
  11
  12 Parameters: <dev path> <offset> <up interval> <down interval>
  13     <dev path>: Full pathname to the underlying block-device, or a
  14                 "major:minor" device-number.
  15     <offset>: Starting sector within the device.
  16     <up interval>: Number of seconds device is available.
  17     <down interval>: Number of seconds device returns errors.