Central calls to ioctl BLKGETSIZE

[thirdparty/mdadm.git] / mdadm.8

diff --git a/mdadm.8 b/mdadm.8
index 076ee637496dfdb64f6d659817bace00978b7d13..b618f5a671a2adaae1819f0ad4e16042cddb2d0b 100644 (file)
--- a/mdadm.8
+++ b/mdadm.8
@@ -5,7 +5,7 @@
 '''   the Free Software Foundation; either version 2 of the License, or
 '''   (at your option) any later version.
 ''' See file COPYING in distribution for details.
 '''   the Free Software Foundation; either version 2 of the License, or
 '''   (at your option) any later version.
 ''' See file COPYING in distribution for details.

-.TH MDADM 8 "" v2.5.3
+.TH MDADM 8 "" v2.5.6

 .SH NAME
 mdadm \- manage MD devices
 .I aka
 .SH NAME
 mdadm \- manage MD devices
 .I aka


@@ -273,6 +273,12 @@ says to get a list of array devices from
 .B -e ", " --metadata=
 Declare the style of superblock (raid metadata) to be used.  The
 default is 0.90 for --create, and to guess for other operations.
 .B -e ", " --metadata=
 Declare the style of superblock (raid metadata) to be used.  The
 default is 0.90 for --create, and to guess for other operations.

+The default can be overridden by setting the
+.B metadata
+value for the
+.B CREATE
+keyword in
+.BR mdadm.conf .

 
 Options are:
 .RS
 
 Options are:
 .RS


@@ -567,6 +573,10 @@ from this.  See DEVICE NAMES below.
 The argument can also come immediately after
 "-a".  e.g. "-ap".
 
 The argument can also come immediately after
 "-a".  e.g. "-ap".
 

+If --auto is not given on the command line or in the config file, then
+the default will be
+.BR --auto=yes .
+

 If
 .I --scan
 is also given, then any
 If
 .I --scan
 is also given, then any


@@ -706,6 +716,7 @@ argument given to this flag can be one of
 .BR homehost ,
 .BR resync ,
 .BR byteorder ,
 .BR homehost ,
 .BR resync ,
 .BR byteorder ,

+.BR devicesize ,

 or
 .BR super-minor .
 
 or
 .BR super-minor .
 


@@ -783,6 +794,22 @@ The
 option will correct the summaries in the superblock. That is the
 counts of total, working, active, failed, and spare devices.
 
 option will correct the summaries in the superblock. That is the
 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
+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
+can be used to store data, so if a device in a version 1.1 or 1.2
+array becomes larger, the metadata will still be visible, but the
+extra space will not.  In this case it might be useful to assemble the
+array with
+.BR --update=devicesize .
+This will cause
+.I mdadm
+to determine the maximum usable amount of space on each device and
+update the relevant field in the metadata.
+

 .TP
 .B --auto-update-homehost
 This flag is only meaning with auto-assembly (see discussion below).
 .TP
 .B --auto-update-homehost
 This flag is only meaning with auto-assembly (see discussion below).


@@ -904,6 +931,14 @@ the exit status of
 .I mdadm
 is set to reflect the status of the device.
 
 .I mdadm
 is set to reflect the status of the device.
 

+.TP
+.BR -W ", " --wait
+For each md device given, wait for any resync, recovery, or reshape
+activity to finish before returning.
+.I mdadm
+will return with success if it actually waited for every device
+listed, otherwise it will return failure.
+

 .SH For Monitor mode:
 .TP
 .BR -m ", " --mail
 .SH For Monitor mode:
 .TP
 .BR -m ", " --mail


@@ -1037,13 +1072,11 @@ may work for RAID1, 4, 5, 6, or 10), give the
 .B --run
 flag.
 
 .B --run
 flag.
 

-If an
-.B auto
-option is given, either on the command line (--auto) or in the
-configuration file (e.g. auto=part), then
-.I mdadm
-will create the md device if necessary or will re-create it if it
-doesn't look usable as it is.
+If the md device does not exist, then it will be created providing the
+intent is clear. i.e. the name must be in a standard form, or the
+.I --auto
+option must be given to clarify how and whether the device should be
+created.

 
 This can be useful for handling partitioned devices (which don't have
 a stable device number - it can change after a reboot) and when using
 
 This can be useful for handling partitioned devices (which don't have
 a stable device number - it can change after a reboot) and when using