Describe the usage of the --rwh-policy parameter in Create and Misc modes. Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@xxxxxxxxx> --- mdadm.8.in | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/mdadm.8.in b/mdadm.8.in index 3c0c58f..9295dcb 100644 --- a/mdadm.8.in +++ b/mdadm.8.in @@ -996,6 +996,26 @@ simultaneously. If not specified, this defaults to 4. Specify journal device for the RAID-4/5/6 array. The journal device should be a SSD with reasonable lifetime. +.TP +.BR \-\-rwh-policy= +Specify the RAID Write Hole policy for a RAID-4/5/6 array. Currently supported +options are +.BR off , +.B journal +and +.BR ppl . + +The +.B journal +policy is implicitly selected when using +.BR \-\-write-journal . + +The +.B ppl +policy (Partial Parity Log) is a mechanism that can be used with RAID5 arrays. +This feature prevents data loss by keeping parity consistent with data even in +case of drive failure during dirty shutdown. PPL is stored in the metadata +region of RAID member drives, no additional journal drive is needed. .SH For assemble: @@ -1675,6 +1695,14 @@ can be found it under .BR "SCRUBBING AND MISMATCHES" . +.TP +.BR \-\-rwh-policy= +Change the RAID Write Hole policy for a RAID-4/5/6 array at runtime. For +details about the RWH policies, see the description for the same parameter +under +.B Create mode +options. + .SH For Incremental Assembly mode: .TP .BR \-\-rebuild\-map ", " \-r -- 2.10.1 -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
