Merge branch 'master' into devel-3.2

[thirdparty/mdadm.git] / mdadm.8.in

diff --git a/mdadm.8.in b/mdadm.8.in
index 00c32dc22286a32119fa6b0e759bea933a5cb870..fed5b62802eaa2351f72f97e29c944f36285179f 100644 (file)
--- a/mdadm.8.in
+++ b/mdadm.8.in
@@ -414,6 +414,9 @@ If this is not specified
 size, though if there is a variance among the drives of greater than 1%, a warning is
 issued.
 
+A suffix of 'M' or 'G' can be given to indicate Megabytes or
+Gigabytes respectively.
+
 This value can be set with
 .B \-\-grow
 for RAID level 1/4/5/6.  If the array was created with a size smaller
@@ -432,7 +435,7 @@ metadata such as DDF and IMSM.
 .BR \-Z ", " \-\-array-size=
 This is only meaningful with
 .B \-\-grow
-and its effect is not persistent: when the array is stopped an
+and its effect is not persistent: when the array is stopped and
 restarted the default array size will be restored.
 
 Setting the array-size causes the array to appear smaller to programs
@@ -443,6 +446,13 @@ but setting the size with
 is, it is required that the array size is reduced as appropriate
 before the number of devices in the array is reduced.
 
+A suffix of 'M' or 'G' can be given to indicate Megabytes or
+Gigabytes respectively.
+A value of
+.B max
+restores the apparent size of the array to be whatever the real
+amount of available space is.
+
 .TP
 .BR \-c ", " \-\-chunk=
 Specify chunk size of kibibytes.  The default when creating an
@@ -450,6 +460,9 @@ array is 512KB.  To ensure compatibility with earlier versions, the
 default when Building and array with no persistent metadata is 64KB.
 This is only meaningful for RAID0, RAID4, RAID5, RAID6, and RAID10.
 
+A suffix of 'M' or 'G' can be given to indicate Megabytes or
+Gigabytes respectively.
+
 .TP
 .BR \-\-rounding=
 Specify rounding factor for a Linear array.  The size of each
@@ -622,6 +635,9 @@ When using an
 bitmap, the chunksize defaults to 64Meg, or larger if necessary to
 fit the bitmap into the available space.
 
+A suffix of 'M' or 'G' can be given to indicate Megabytes or
+Gigabytes respectively.
+
 .TP
 .BR \-W ", " \-\-write\-mostly
 subsequent devices listed in a
@@ -670,21 +686,6 @@ or layout.  See the GROW MODE section below on RAID\-DEVICES CHANGES.
 The file must 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
@@ -887,15 +888,25 @@ bitmap, there is no need to specify this when assembling the array.
 .BR \-\-backup\-file=
 If
 .B \-\-backup\-file
-was used when requesting a grow, shrink, RAID level change or other
-reshape, and the system crashed during the critical section, then the
-same
+was used while reshaping an array (e.g. changing number of devices or
+chunk size) and the system crashed during the critical section, then the same
 .B \-\-backup\-file
 must be presented to
 .B \-\-assemble
 to allow possibly corrupted data to be restored, and the reshape
 to be completed.
 
+.TP
+.BR \-\-invalid\-backup
+If the file needed for the above option is not available for any
+reason an empty file can be given together with this option to
+indicate that the backup file is invalid.  In this case the data that
+was being rearranged at the time of the crash could be irrecoverably
+lost, but the rest of the array may still be recoverable.  This option
+should only be used as a last resort if there is no way to recover the
+backup file.
+
+
 .TP
 .BR \-U ", " \-\-update=
 Update the superblock on each device while assembling the array.  The
@@ -908,6 +919,7 @@ argument given to this flag can be one of
 .BR resync ,
 .BR byteorder ,
 .BR devicesize ,
+.BR no\-bitmap ,
 or
 .BR super\-minor .
 
@@ -990,7 +1002,7 @@ counts of total, working, active, failed, and spare devices.
 
 The
 .B devicesize
-will rarely be of use.  It applies to version 1.1 and 1.2 metadata
+option will rarely be of use.  It applies to version 1.1 and 1.2 metadata
 only (where the metadata is at the start of the device) and is only
 useful when the component device has changed size (typically become
 larger).  The version 1 metadata records the amount of the device that
@@ -1004,6 +1016,12 @@ This will cause
 to determine the maximum usable amount of space on each device and
 update the relevant field in the metadata.
 
+The
+.B no\-bitmap
+option can be used when an array has an internal bitmap which is
+corrupt in some way so that assembling the array normally fails.  It
+will cause any internal bitmap to be ignored.
+
 .ig
 .TP
 .B \-\-auto\-update\-homehost