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Merging upstream version 4.3+20241108.

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Signed-off-by: Daniel Baumann <daniel@debian.org>
This commit is contained in:
Daniel Baumann 2025-02-14 06:11:53 +01:00
parent 1e24552bfc
commit 60ccb5b596
Signed by: daniel
GPG key ID: FBB4F0E80A80222F
64 changed files with 2015 additions and 1768 deletions
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mdadm.8.in
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@ -48,11 +48,12 @@ multiple devices:
each device is a path to one common physical storage device.
New installations should not use md/multipath as it is not well
supported and has no ongoing development. Use the Device Mapper based
multipath-tools instead.
multipath-tools instead. It is deprecated and support will be removed in the future.
.B FAULTY
is also not true RAID, and it only involves one device. It
provides a layer over a true device that can be used to inject faults.
provides a layer over a true device that can be used to inject faults. It is deprecated
and support will be removed in the future.
.B CONTAINER
is different again. A
@ -354,7 +355,7 @@ preferred 1.x format).
'if '{DEFAULT_METADATA}'1.2' "default" is equivalent to "1.2".
.IP ddf
Use the "Industry Standard" DDF (Disk Data Format) format defined by
SNIA.
SNIA. DDF is deprecated and there is no active development around it.
When creating a DDF array a
.B CONTAINER
will be created, and normal arrays can be created in that container.
@ -443,8 +444,7 @@ multipath, RAID0 and RAID1. It is never allowed for RAID4, RAID5 or RAID6.
.br
This number can only be changed using
.B \-\-grow
for RAID1, RAID4, RAID5 and RAID6 arrays, and only on kernels which provide
the necessary support.
for RAID1, RAID4, RAID5 and RAID6 arrays.
.TP
.BR \-x ", " \-\-spare\-devices=
@ -563,8 +563,7 @@ component will be rounded down to a multiple of this size.
This is a synonym for
.B \-\-chunk
but highlights the different meaning for Linear as compared to other
RAID levels. The default is 64K if a kernel earlier than 2.6.16 is in
use, and is 0K (i.e. no rounding) in later kernels.
RAID levels. The default is 0K (i.e. no rounding).
.TP
.BR \-l ", " \-\-level=
@ -829,7 +828,7 @@ facts the operator knows.
When an array is resized to a larger size with
.B "\-\-grow \-\-size="
the new space is normally resynced in that same way that the whole
array is resynced at creation. From Linux version 3.0,
array is resynced at creation.
.B \-\-assume\-clean
can be used with that command to avoid the automatic resync.
@ -837,8 +836,7 @@ can be used with that command to avoid the automatic resync.
.BR \-\-write-zeroes
When creating an array, send write zeroes requests to all the block
devices. This should zero the data area on all disks such that the
initial sync is not necessary and, if successfull, will behave
as if
initial sync is not necessary and, if successful, will behave as if
.B \-\-assume\-clean
was specified.
.IP
@ -875,7 +873,6 @@ Setting the offset explicitly over-rides the default. The value given
is in Kilobytes unless a suffix of 'K', 'M', 'G' or 'T' is used to explicitly
indicate Kilobytes, Megabytes, Gigabytes or Terabytes respectively.
Since Linux 3.4,
.B \-\-data\-offset
can also be used with
.B --grow
@ -968,63 +965,6 @@ rather than read-write as normal. No writes will be allowed to the
array, and no resync, recovery, or reshape will be started. It works with
Create, Assemble, Manage and Misc mode.
.TP
.BR \-a ", " "\-\-auto{=yes,md,mdp,part,p}{NN}"
Instruct mdadm how to create the device file if needed, possibly allocating
an unused minor number. "md" causes a non-partitionable array
to be used (though since Linux 2.6.28, these array devices are in fact
partitionable). "mdp", "part" or "p" causes a partitionable array (2.6 and
later) to be used. "yes" requires the named md device to have
a 'standard' format, and the type and minor number will be determined
from this. With mdadm 3.0, device creation is normally left up to
.I udev
so this option is unlikely to be needed.
See DEVICE NAMES below.
The argument can also come immediately after
"\-a". e.g. "\-ap".
If
.B \-\-auto
is not given on the command line or in the config file, then
the default will be
.BR \-\-auto=yes .
If
.B \-\-scan
is also given, then any
.I auto=
entries in the config file will override the
.B \-\-auto
instruction given on the command line.
For partitionable arrays,
.I mdadm
will create the device file for the whole array and for the first 4
partitions. A different number of partitions can be specified at the
end of this option (e.g.
.BR \-\-auto=p7 ).
If the device name ends with a digit, the partition names add a 'p',
and a number, e.g.
.IR /dev/md/home1p3 .
If there is no trailing digit, then the partition names just have a
number added, e.g.
.IR /dev/md/scratch3 .
If the md device name is in a 'standard' format as described in DEVICE
NAMES, then it will be created, if necessary, with the appropriate
device number based on that name. If the device name is not in one of these
formats, then an unused device number will be allocated. The device
number will be considered unused if there is no active array for that
number, and there is no entry in /dev for that number and with a
non-standard name. Names that are not in 'standard' format are only
allowed in "/dev/md/".
This is meaningful with
.B \-\-create
or
.BR \-\-build .
.TP
.BR \-a ", " "\-\-add"
This option can be used in Grow mode in two cases.
@ -1168,10 +1108,6 @@ are present. This is only needed with
and can be used if the physical connections to devices are
not as reliable as you would like.
.TP
.BR \-a ", " "\-\-auto{=no,yes,md,mdp,part}"
See this option under Create and Build options.
.TP
.BR \-b ", " \-\-bitmap=
Specify the bitmap file that was given when the array was created. If
@ -1206,7 +1142,6 @@ backup file.
.BR \-U ", " \-\-update=
Update the superblock on each device while assembling the array. The
argument given to this flag can be one of
.BR sparc2.2 ,
.BR summaries ,
.BR uuid ,
.BR name ,
@ -1228,16 +1163,6 @@ argument given to this flag can be one of
or
.BR super\-minor .
The
.B sparc2.2
option will adjust the superblock of an array what was created on a Sparc
machine running a patched 2.2 Linux kernel. This kernel got the
alignment of part of the superblock wrong. You can use the
.B "\-\-examine \-\-sparc2.2"
option to
.I mdadm
to see what effect this would have.
The
.B super\-minor
option will update the
@ -1251,7 +1176,7 @@ reports a different "Preferred Minor" to
In some cases this update will be performed automatically
by the kernel driver. In particular, the update happens automatically
at the first write to an array with redundancy (RAID level 1 or
greater) on a 2.6 (or later) kernel.
greater).
The
.B uuid
@ -1686,18 +1611,6 @@ and
applies to devices which are components of an array, while
.B \-\-detail
applies to a whole array which is currently active.
.TP
.B \-\-sparc2.2
If an array was created on a SPARC machine with a 2.2 Linux kernel
patched with RAID support, the superblock will have been created
incorrectly, or at least incompatibly with 2.4 and later kernels.
Using the
.B \-\-sparc2.2
flag with
.B \-\-examine
will fix the superblock before displaying it. If this appears to do
the right thing, then the array can be successfully assembled using
.BR "\-\-assemble \-\-update=sparc2.2" .
.TP
.BR \-X ", " \-\-examine\-bitmap
@ -1830,6 +1743,16 @@ can be found it
under
.BR "SCRUBBING AND MISMATCHES" .
.TP
.B \-\-udev\-rules=
it generates the udev rules to the file that handles hot-plug bare devices.
Given the POLICYs defined under
.IR {CONFFILE}\ (or {CONFFILE2})
See
.BR mdadm.conf (5)
for more details and usage examples about POLICY.
.SH For Incremental Assembly mode:
.TP
.BR \-\-rebuild\-map ", " \-r
@ -1878,11 +1801,15 @@ script.
.SH For Monitor mode:
.TP
.BR \-m ", " \-\-mail
Give a mail address to send alerts to.
Give an mail address to send alerts to. Can be configured in
.B mdadm.conf
as MAILADDR.
.TP
.BR \-p ", " \-\-program ", " \-\-alert
Give a program to be run whenever an event is detected.
Give a program to be run whenever an event is detected. Can be configured in
.B mdadm.conf
as PROGRAM.
.TP
.BR \-y ", " \-\-syslog
@ -1891,13 +1818,12 @@ facility of 'daemon' and varying priorities.
.TP
.BR \-d ", " \-\-delay
Give a delay in seconds.
Give a delay in seconds. The default is 60 seconds.
.I mdadm
polls the md arrays and then waits this many seconds before polling
again. The default is 60 seconds. Since 2.6.16, there is no need to
reduce this as the kernel alerts
.I mdadm
immediately when there is any change.
polls the md arrays and then waits this many seconds before polling again if no event happened.
Can be configured in
.B mdadm.conf
as MONITORDELAY.
.TP
.BR \-r ", " \-\-increment
@ -2050,33 +1976,6 @@ detects that udev is not configured, it will create the devices in
.B /dev
itself.
In Linux kernels prior to version 2.6.28 there were two distinct
types of md devices that could be created: one that could be
partitioned using standard partitioning tools and one that could not.
Since 2.6.28 that distinction is no longer relevant as both types of
devices can be partitioned.
.I mdadm
will normally create the type that originally could not be partitioned
as it has a well-defined major number (9).
Prior to 2.6.28, it is important that mdadm chooses the correct type
of array device to use. This can be controlled with the
.B \-\-auto
option. In particular, a value of "mdp" or "part" or "p" tells mdadm
to use a partitionable device rather than the default.
In the no-udev case, the value given to
.B \-\-auto
can be suffixed by a number. This tells
.I mdadm
to create that number of partition devices rather than the default of 4.
The value given to
.B \-\-auto
can also be given in the configuration file as a word starting
.B auto=
on the ARRAY line for the relevant array.
.SS Auto-Assembly
When
.B \-\-assemble
@ -2595,30 +2494,29 @@ is given, then a
.B program
or an
.B e-mail
address must be specified on the
command line or in the config file. If neither are available, then
address must be specified on the command line or in the config file. If neither are available, then
.I mdadm
will not monitor anything.
For devices given directly in command line, without
will not monitor anything. For devices given directly in command line, without
.B program
or
.B email
specified, each event is reported to
.BR stdout.
Note: For systems where
.If mdadm monitor
is configured via systemd,
.B mdmonitor(mdmonitor.service)
should be configured. The service is designed to be primary solution for array monitoring,
it is configured to work in system wide mode.
It is automatically started and stopped according to current state and types of MD arrays in system.
The service may require additional configuration, like
.B e-mail
or
.B delay.
That should be done in
.B mdadm.conf.
Note: On systems where mdadm monitoring is managed through systemd, the mdmonitor.service
should be present. This service is designed to be the primary solution for array monitoring.
It is configured to operate in system-wide mode. It is initiated by udev when start criteria are
met, e.g.
.B mdadm.conf
exists and necessary configuration parameters are set.
It is kept alive as long as a redundant RAID array is active; it stops otherwise. User should
customize MAILADDR in
.B mdadm.conf
to receive mail notifications. MONITORDELAY, MAILFROM and PROGRAM are optional. See
.BR mdadm.conf (5)
for detailed description of these options.
Use systemctl status mdmonitor.service to verify status or determine if additional configuration
is needed.
The different events are:
@ -2774,7 +2672,7 @@ and then follow similar steps as above if a matching spare is found.
The GROW mode is used for changing the size or shape of an active
array.
During the kernel 2.6 era the following changes were added:
The following changes are supported:
.IP \(bu 4
change the "size" attribute for RAID1, RAID4, RAID5 and RAID6.
.IP \(bu 4
@ -2858,14 +2756,12 @@ When the number of devices is increased, any hot spares that are
present will be activated immediately.
Changing the number of active devices in a RAID5 or RAID6 is much more
effort. Every block in the array will need to be read and written
back to a new location. From 2.6.17, the Linux Kernel is able to
increase the number of devices in a RAID5 safely, including restarting
an interrupted "reshape". From 2.6.31, the Linux Kernel is able to
increase or decrease the number of devices in a RAID5 or RAID6.
effort. Every block in the array will need to be read and written
back to a new location. Linux Kernel is able to increase or decrease
the number of devices in a RAID5 and RAID6 safely, including restarting
an interrupted "reshape".
From 2.6.35, the Linux Kernel is able to convert a RAID0 in to a RAID4
or RAID5.
The Linux Kernel is able to convert a RAID0 into a RAID4 or RAID5.
.I mdadm
uses this functionality and the ability to add
devices to a RAID4 to allow devices to be added to a RAID0. When
@ -3419,26 +3315,14 @@ Also if the homehost is specified as
will only use a suffix if a different array of the same name already
exists or is listed in the config file.
The standard names for non-partitioned arrays (the only sort of md
array available in 2.4 and earlier) are of the form
The names for arrays are of the form:
.IP
.RB /dev/md NN
.PP
where NN is a number.
The standard names for partitionable arrays (as available from 2.6
onwards) are of the form:
.IP
.RB /dev/md_d NN
.PP
Partition numbers should be indicated by adding "pMM" to these, thus "/dev/md/d1p2".
.PP
From kernel version 2.6.28 the "non-partitioned array" can actually
be partitioned. So the "md_d\fBNN\fP"
names are no longer needed, and
partitions such as "/dev/md\fBNN\fPp\fBXX\fP"
are possible.
.PP
From kernel version 2.6.29 standard names can be non-numeric following
Names can be non-numeric following
the form:
.IP
.RB /dev/md_ XXX