Grow: support --array-size changes

[thirdparty/mdadm.git] / mdadm.8

diff --git a/mdadm.8 b/mdadm.8
index 3b4f47d8264368881c26616436803d892f80196e..079914feeccfbcd38367de4580710a2cf37e8a70 100644 (file)
--- a/mdadm.8
+++ b/mdadm.8
@@ -593,6 +593,21 @@ raid-devices in a RAID5 if there  are no spare devices available.
 See the section below on RAID_DEVICE CHANGES.  The file should be
 stored on a separate device, not on the raid array being reshaped.
 
+.TP
+.BR \-\-array-size= ", " \-Z
+Set the size of the array which is seen by users of the device such as
+filesystems.  This can be less that the real size, but never greater.
+The size set this way does not persist across restarts of the array.
+
+This is most useful when reducing the number of devices in a RAID5 or
+RAID6.  Such arrays require the array-size to be reduced before a
+reshape can be performed that reduces the real size.
+
+A value of
+.B max
+restores the apparent size of the array to be whatever the real
+amount of available space is.
+
 .TP
 .BR \-N ", " \-\-name=
 Set a