+++ /dev/null
-.\" Copyright Neil Brown and others.
-.\" This program is free software; you can redistribute it and/or modify
-.\" it under the terms of the GNU General Public License as published by
-.\" 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.CONF 5
-.SH NAME
-mdadm.conf \- configuration for management of Software RAID with mdadm
-.SH SYNOPSIS
-/etc/mdadm.conf
-.SH DESCRIPTION
-.PP
-.I mdadm
-is a tool for creating, managing, and monitoring RAID devices using the
-.B md
-driver in Linux.
-.PP
-Some common tasks, such as assembling all arrays, can be simplified
-by describing the devices and arrays in this configuration file.
-
-.SS SYNTAX
-The file should be seen as a collection of words separated by white
-space (space, tab, or newline).
-Any word that beings with a hash sign (#) starts a comment and that
-word together with the remainder of the line is ignored.
-
-Spaces can be included in a word using quotation characters. Either
-single quotes
-.RB ( ' )
-or double quotes (\fB"\fP)
-may be used. All the characters from one quotation character to
-next identical character are protected and will not be used to
-separate words to start new quoted strings. To include a single quote
-it must be between double quotes. To include a double quote it must
-be between single quotes.
-
-Any line that starts with white space (space or tab) is treated as
-though it were a continuation of the previous line.
-
-Empty lines are ignored, but otherwise each (non continuation) line
-must start with a keyword as listed below. The keywords are case
-insensitive and can be abbreviated to 3 characters.
-
-The keywords are:
-.TP
-.B DEVICE
-A
-.B device
-line lists the devices (whole devices or partitions) that might contain
-a component of an MD array. When looking for the components of an
-array,
-.I mdadm
-will scan these devices (or any devices listed on the command line).
-
-The
-.B device
-line may contain a number of different devices (separated by spaces)
-and each device name can contain wild cards as defined by
-.BR glob (7).
-
-Also, there may be several device lines present in the file.
-
-Alternatively, a
-.B device
-line can contain either or both of the words
-.B containers
-and
-.BR partitions .
-The word
-.B containers
-will cause
-.I mdadm
-to look for assembled CONTAINER arrays and included them as a source
-for assembling further arrays.
-
-The word
-.I partitions
-will cause
-.I mdadm
-to read
-.I /proc/partitions
-and include all devices and partitions found therein.
-.I mdadm
-does not use the names from
-.I /proc/partitions
-but only the major and minor device numbers. It scans
-.I /dev
-to find the name that matches the numbers.
-
-If no DEVICE line is present, then "DEVICE partitions containers" is assumed.
-
-For example:
-.IP
-DEVICE /dev/hda* /dev/hdc*
-.br
-DEV /dev/sd*
-.br
-DEVICE /dev/disk/by-path/pci*
-.br
-DEVICE partitions
-
-.TP
-.B ARRAY
-The ARRAY lines identify actual arrays. The second word on the line
-may be the name of the device where the array is normally
-assembled, such as
-.B /dev/md1
-or
-.BR /dev/md/backup .
-If the name does not start with a slash
-.RB (' / '),
-it is treated as being in
-.BR /dev/md/ .
-Alternately the word
-.B <ignore>
-(complete with angle brackets) can be given in which case any array
-which matches the rest of the line will never be automatically assembled.
-If no device name is given,
-.I mdadm
-will use various heuristics to determine an appropriate name.
-
-Subsequent words identify the array, or identify the array as a member
-of a group. If multiple identities are given,
-then a component device must match ALL identities to be considered a
-match. Each identity word has a tag, and equals sign, and some value.
-The tags are:
-.RS 4
-.TP
-.B uuid=
-The value should be a 128 bit uuid in hexadecimal, with punctuation
-interspersed if desired. This must match the uuid stored in the
-superblock.
-.TP
-.B name=
-The value should be a simple textual name as was given to
-.I mdadm
-when the array was created. This must match the name stored in the
-superblock on a device for that device to be included in the array.
-Not all superblock formats support names.
-.TP
-.B super\-minor=
-The value is an integer which indicates the minor number that was
-stored in the superblock when the array was created. When an array is
-created as /dev/mdX, then the minor number X is stored.
-.TP
-.B devices=
-The value is a comma separated list of device names or device name
-patterns.
-Only devices with names which match one entry in the list will be used
-to assemble the array. Note that the devices
-listed there must also be listed on a DEVICE line.
-.TP
-.B level=
-The value is a RAID level. This is not normally used to
-identify an array, but is supported so that the output of
-
-.B "mdadm \-\-examine \-\-scan"
-
-can be use directly in the configuration file.
-.TP
-.B num\-devices=
-The value is the number of devices in a complete active array. As with
-.B level=
-this is mainly for compatibility with the output of
-
-.BR "mdadm \-\-examine \-\-scan" .
-
-.TP
-.B spares=
-The value is a number of spare devices to expect the array to have.
-The sole use of this keyword and value is as follows:
-.B mdadm \-\-monitor
-will report an array if it is found to have fewer than this number of
-spares when
-.B \-\-monitor
-starts or when
-.B \-\-oneshot
-is used.
-
-.TP
-.B spare\-group=
-The value is a textual name for a group of arrays. All arrays with
-the same
-.B spare\-group
-name are considered to be part of the same group. The significance of
-a group of arrays is that
-.I mdadm
-will, when monitoring the arrays, move a spare drive from one array in
-a group to another array in that group if the first array had a failed
-or missing drive but no spare.
-
-.TP
-.B auto=
-This option is rarely needed with mdadm-3.0, particularly if use with
-the Linux kernel v2.6.28 or later.
-It tells
-.I mdadm
-whether to use partitionable array or non-partitionable arrays and,
-in the absence of
-.IR udev ,
-how many partition devices to create. From 2.6.28 all md array
-devices are partitionable, hence this option is not needed.
-
-The value of this option can be "yes" or "md" to indicate that a
-traditional, non-partitionable md array should be created, or "mdp",
-"part" or "partition" to indicate that a partitionable md array (only
-available in linux 2.6 and later) should be used. This later set can
-also have a number appended to indicate how many partitions to create
-device files for, e.g.
-.BR auto=mdp5 .
-The default is 4.
-
-.TP
-.B bitmap=
-The option specifies a file in which a write-intent bitmap should be
-found. When assembling the array,
-.I mdadm
-will provide this file to the
-.B md
-driver as the bitmap file. This has the same function as the
-.B \-\-bitmap\-file
-option to
-.BR \-\-assemble .
-
-.TP
-.B metadata=
-Specify the metadata format that the array has. This is mainly
-recognised for comparability with the output of
-.BR "mdadm \-Es" .
-
-.TP
-.B container=
-Specify that this array is a member array of some container. The
-value given can be either a path name in /dev, or a UUID of the
-container array.
-
-.TP
-.B member=
-Specify that this array is a member array of some container. Each
-type of container has some way to enumerate member arrays, often a
-simple sequence number. The value identifies which member of a
-container the array is. It will usually accompany a "container=" word.
-.RE
-
-.TP
-.B MAILADDR
-The
-.B mailaddr
-line gives an E-mail address that alerts should be
-sent to when
-.I mdadm
-is running in
-.B \-\-monitor
-mode (and was given the
-.B \-\-scan
-option). There should only be one
-.B MAILADDR
-line and it should have only one address. Any subsequent addresses
-are silently ignored.
-
-.TP
-.B MAILFROM
-The
-.B mailfrom
-line (which can only be abbreviated to at least 5 characters) gives an
-address to appear in the "From" address for alert mails. This can be
-useful if you want to explicitly set a domain, as the default from
-address is "root" with no domain. All words on this line are
-catenated with spaces to form the address.
-
-Note that this value cannot be set via the
-.I mdadm
-commandline. It is only settable via the config file.
-
-.TP
-.B PROGRAM
-The
-.B program
-line gives the name of a program to be run when
-.B "mdadm \-\-monitor"
-detects potentially interesting events on any of the arrays that it
-is monitoring. This program gets run with two or three arguments, they
-being the Event, the md device, and possibly the related component
-device.
-
-There should only be one
-.B program
-line and it should be give only one program.
-
-
-.TP
-.B CREATE
-The
-.B create
-line gives default values to be used when creating arrays, new members
-of arrays, and device entries for arrays.
-These include:
-
-.RS 4
-.TP
-.B owner=
-.TP
-.B group=
-These can give user/group ids or names to use instead of system
-defaults (root/wheel or root/disk).
-.TP
-.B mode=
-An octal file mode such as 0660 can be given to override the default
-of 0600.
-.TP
-.B auto=
-This corresponds to the
-.B \-\-auto
-flag to mdadm. Give
-.BR yes ,
-.BR md ,
-.BR mdp ,
-.B part
-\(em possibly followed by a number of partitions \(em to indicate how
-missing device entries should be created.
-
-.TP
-.B metadata=
-The name of the metadata format to use if none is explicitly given.
-This can be useful to impose a system-wide default of version-1 superblocks.
-
-.TP
-.B symlinks=no
-Normally when creating devices in
-.B /dev/md/
-.I mdadm
-will create a matching symlink from
-.B /dev/
-with a name starting
-.B md
-or
-.BR md_ .
-Give
-.B symlinks=no
-to suppress this symlink creation.
-
-.TP
-.B names=yes
-Since Linux 2.6.29 it has been possible to create
-.B md
-devices with a name like
-.B md_home
-rather than just a number, like
-.BR md3 .
-.I mdadm
-will use the numeric alternative by default as other tools that interact
-with md arrays may expect only numbers.
-If
-.B names=yes
-is given in
-.I mdadm.conf
-then
-.I mdadm
-will use a name when appropriate.
-If
-.B names=no
-is given, then non-numeric
-.I md
-device names will not be used even if the default changes in a future
-release of
-.IR mdadm .
-
-.TP
-.B bbl=no
-By default,
-.I mdadm
-will reserve space for a bad block list (bbl) on all devices
-included in or added to any array that supports them. Setting
-.B bbl=no
-will prevent this, so newly added devices will not have a bad
-block log.
-.RE
-
-.TP
-.B HOMEHOST
-The
-.B homehost
-line gives a default value for the
-.B \-\-homehost=
-option to mdadm. There should normally be only one other word on the line.
-It should either be a host name, or one of the special words
-.BR <system>,
-.B <none>
-and
-.BR <ignore> .
-If
-.B <system>
-is given, then the
-.BR gethostname ( 2 )
-systemcall is used to get the host name. This is the default.
-
-If
-.B <ignore>
-is given, then a flag is set so that when arrays are being
-auto-assembled the checking of the recorded
-.I homehost
-is disabled.
-If
-.B <ignore>
-is given it is also possible to give an explicit name which will be
-used when creating arrays. This is the only case when there can be
-more that one other word on the
-.B HOMEHOST
-line. If there are other words, or other
-.B HOMEHOST
-lines, they are silently ignored.
-
-If
-.B <none>
-is given, then the default of using
-.BR gethostname ( 2 )
-is over-ridden and no homehost name is assumed.
-
-When arrays are created, this host name will be stored in the
-metadata. When arrays are assembled using auto-assembly, arrays which
-do not record the correct homehost name in their metadata will be
-assembled using a "foreign" name. A "foreign" name alway ends with a
-digit string preceded by an underscore to differentiate it
-from any possible local name. e.g.
-.B /dev/md/1_1
-or
-.BR /dev/md/home_0 .
-.TP
-.B AUTO
-A list of names of metadata format can be given, each preceded by a
-plus or minus sign. Also the word
-.I homehost
-is allowed as is
-.I all
-preceded by plus or minus sign.
-.I all
-is usually last.
-
-When
-.I mdadm
-is auto-assembling an array, either via
-.I \-\-assemble
-or
-.I \-\-incremental
-and it finds metadata of a given type, it checks that metadata type
-against those listed in this line. The first match wins, where
-.I all
-matches anything.
-If a match is found that was preceded by a plus sign, the auto
-assembly is allowed. If the match was preceded by a minus sign, the
-auto assembly is disallowed. If no match is found, the auto assembly
-is allowed.
-
-If the metadata indicates that the array was created for
-.I this
-host, and the word
-.I homehost
-appears before any other match, then the array is treated as a valid
-candidate for auto-assembly.
-
-This can be used to disable all auto-assembly (so that only arrays
-explicitly listed in mdadm.conf or on the command line are assembled),
-or to disable assembly of certain metadata types which might be
-handled by other software. It can also be used to disable assembly of
-all foreign arrays - normally such arrays are assembled but given a
-non-deterministic name in
-.BR /dev/md/ .
-
-The known metadata types are
-.BR 0.90 ,
-.BR 1.x ,
-.BR ddf ,
-.BR imsm .
-
-.B AUTO
-should be given at most once. Subsequent lines are silently ignored.
-Thus an earlier config file in a config directory will over-ride
-the setting in a later config file.
-
-.TP
-.B POLICY
-This is used to specify what automatic behavior is allowed on devices
-newly appearing in the system and provides a way of marking spares that can
-be moved to other arrays as well as the migration domains.
-.I Domain
-can be defined through
-.I policy
-line by specifying a domain name for a number of paths from
-.BR /dev/disk/by-path/ .
-A device may belong to several domains. The domain of an array is a union
-of domains of all devices in that array. A spare can be automatically
-moved from one array to another if the set of the destination array's
-.I domains
-contains all the
-.I domains
-of the new disk or if both arrays have the same
-.IR spare-group .
-
-To update hot plug configuration it is necessary to execute
-.B mdadm \-\-udev\-rules
-command after changing the config file
-
-Keywords used in the
-.I POLICY
-line and supported values are:
-
-.RS 4
-.TP
-.B domain=
-any arbitrary string
-.TP
-.B metadata=
-0.9 1.x ddf or imsm
-.TP
-.B path=
-file glob matching anything from
-.B /dev/disk/by-path
-.TP
-.B type=
-either
-.B disk
-or
-.BR part .
-.TP
-.B action=
-include, re-add, spare, spare-same-slot, or force-spare
-.TP
-.B auto=
-yes, no, or homehost.
-
-.P
-The
-.I action
-item determines the automatic behavior allowed for devices matching the
-.I path
-and
-.I type
-in the same line. If a device matches several lines with different
-.I actions
-then the most permissive will apply. The ordering of policy lines
-is irrelevant to the end result.
-.TP
-.B include
-allows adding a disk to an array if metadata on that disk matches that array
-.TP
-.B re\-add
-will include the device in the array if it appears to be a current member
-or a member that was recently removed and the array has a
-write-intent-bitmap to allow the
-.B re\-add
-functionality.
-.TP
-.B spare
-as above and additionally: if the device is bare it can
-become a spare if there is any array that it is a candidate for based
-on domains and metadata.
-.TP
-.B spare\-same\-slot
-as above and additionally if given slot was used by an array that went
-degraded recently and the device plugged in has no metadata then it will
-be automatically added to that array (or it's container)
-.TP
-.B force\-spare
-as above and the disk will become a spare in remaining cases
-.RE
-
-.TP
-.B PART-POLICY
-This is similar to
-.B POLICY
-and accepts the same keyword assignments. It allows a consistent set
-of policies to applied to each of the partitions of a device.
-
-A
-.B PART-POLICY
-line should set
-.I type=disk
-and identify the path to one or more disk devices. Each partition on
-these disks will be treated according to the
-.I action=
-setting from this line. If a
-.I domain
-is set in the line, then the domain associated with each patition will
-be based on the domain, but with
-.RB \(dq -part N\(dq
-appended, when N is the partition number for the partition that was
-found.
-
-.TP
-.B SYSFS
-The
-.B SYSFS
-line lists custom values of MD device's sysfs attributes which will be
-stored in sysfs after the array is assembled. Multiple lines are allowed and each
-line has to contain the uuid or the name of the device to which it relates.
-.RS 4
-.TP
-.B uuid=
-hexadecimal identifier of MD device. This has to match the uuid stored in the
-superblock.
-.TP
-.B name=
-name of the MD device as was given to
-.I mdadm
-when the array was created. It will be ignored if
-.B uuid
-is not empty.
-.RE
-
-.TP
-.B MONITORDELAY
-The
-.B monitordelay
-line gives a delay in seconds
-.I mdadm
-shall wait before pooling md arrays
-when
-.I mdadm
-is running in
-.B \-\-monitor
-mode.
-.B \-d/\-\-delay
-command line argument takes precedence over the config file
-
-.SH EXAMPLE
-DEVICE /dev/sd[bcdjkl]1
-.br
-DEVICE /dev/hda1 /dev/hdb1
-
-# /dev/md0 is known by its UUID.
-.br
-ARRAY /dev/md0 UUID=3aaa0122:29827cfa:5331ad66:ca767371
-.br
-# /dev/md1 contains all devices with a minor number of
-.br
-# 1 in the superblock.
-.br
-ARRAY /dev/md1 superminor=1
-.br
-# /dev/md2 is made from precisely these two devices
-.br
-ARRAY /dev/md2 devices=/dev/hda1,/dev/hdb1
-
-# /dev/md4 and /dev/md5 are a spare-group and spares
-.br
-# can be moved between them
-.br
-ARRAY /dev/md4 uuid=b23f3c6d:aec43a9f:fd65db85:369432df
-.br
- spare\-group=group1
-.br
-ARRAY /dev/md5 uuid=19464854:03f71b1b:e0df2edd:246cc977
-.br
- spare\-group=group1
-.br
-# /dev/md/home is created if need to be a partitionable md array
-.br
-# any spare device number is allocated.
-.br
-ARRAY /dev/md/home UUID=9187a482:5dde19d9:eea3cc4a:d646ab8b
-.br
- auto=part
-.br
-# The name of this array contains a space.
-.br
-ARRAY /dev/md9 name='Data Storage'
-.sp
-POLICY domain=domain1 metadata=imsm path=pci-0000:00:1f.2-scsi-*
-.br
- action=spare
-.br
-POLICY domain=domain1 metadata=imsm path=pci-0000:04:00.0-scsi-[01]*
-.br
- action=include
-.br
-# One domain comprising of devices attached to specified paths is defined.
-.br
-# Bare device matching first path will be made an imsm spare on hot plug.
-.br
-# If more than one array is created on devices belonging to domain1 and
-.br
-# one of them becomes degraded, then any imsm spare matching any path for
-.br
-# given domain name can be migrated.
-.br
-MAILADDR root@mydomain.tld
-.br
-PROGRAM /usr/sbin/handle\-mdadm\-events
-.br
-CREATE group=system mode=0640 auto=part\-8
-.br
-HOMEHOST <system>
-.br
-AUTO +1.x homehost \-all
-.br
-SYSFS name=/dev/md/raid5 group_thread_cnt=4 sync_speed_max=1000000
-.br
-SYSFS uuid=bead5eb6:31c17a27:da120ba2:7dfda40d group_thread_cnt=4
-sync_speed_max=1000000
-.br
-MONITORDELAY 60
-
-.SH SEE ALSO
-.BR mdadm (8),
-.BR md (4).
projects / thirdparty / mdadm.git / blobdiff