linux/Documentation/device-mapper/dm-flakey.txt
Josef Bacik 3407ef5262 dm: add flakey target
This target is the same as the linear target except that it returns I/O
errors periodically.  It's been found useful in simulating failing
devices for testing purposes.

I needed a dm target to do some failure testing on btrfs's raid code, and
Mike pointed me at this.

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-03-24 13:54:24 +00:00

18 lines
708 B
Plaintext

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