-''' 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.
+.\" 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
+mdadm.conf \- configuration for management of Software RAID with mdadm
.SH SYNOPSIS
/etc/mdadm.conf
.SH DESCRIPTION
.PP
-.B mdadm
+.I mdadm
is a tool for creating, managing, and monitoring RAID devices using the
.B md
driver in Linux.
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,
-.B mdadm
+.I mdadm
will scan these devices (or any devices listed on the command line).
The
Alternatively, a
.B device
-line can contain the word
+line can contain either of both of the words
+.B containers
+and
.BR partitions .
-This will cause
+The word
+.B containers
+will cause
+.I mdadm
+to look for assembled CONTAINER arrays and included them as a source
+for assembling further arrays.
+.PP
+The word
+.I partitions
+will cause
.I mdadm
to read
.I /proc/partitions
.I /dev
to find the name that matches the numbers.
-If no DEVICE line is present, then "DEVICE partitions" is assumed.
+If no DEVICE line is present, then "DEVICE partitions containers" is assumed.
For example:
.IP
.TP
.B ARRAY
The ARRAY lines identify actual arrays. The second word on the line
-should be the name of the device where the array is normally
+may be the name of the device where the array is normally
assembled, such as
.BR /dev/md1 .
+If no device name is given,
+.I mdadm
+will use various heuristic to determine an appropriate name.
+.PP
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
.B spare\-group
name are considered to be part of the same group. The significance of
a group of arrays is that
-.B mdadm
+.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 declares to
-.B mdadm
+.I mdadm
that it should try to create the device file of the array if it
doesn't already exist, or exists but with the wrong device number.
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.
+
+.IP
+.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
line gives an E-mail address that alerts should be
sent to when
-.M mdadm
+.I mdadm
is running in
.B \-\-monitor
mode (and was given the
.B MAILFROM
The
.B mailfrom
-line (which can only be abbreviate at leat 5 characters) gives an
+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
to suppress this symlink creation.
.RE
+.TP
+.B HOMEHOST
+The
+.B homehost
+line gives a default value for the
+.B --homehost=
+option to mdadm. There should be exactly one other word on the line.
+It should either exactly
+.B <system>
+or a host name.
+If
+.B <system>
+is given, then the
+.BR gethostname ( 2 )
+systemcall is used to get the host name.
+When arrays are created, this host name will be stored in the
+metadata. When arrays are assembled using auto-assembly, only arrays
+with this host name stored in the metadata will be considered.
.SH EXAMPLE
DEVICE /dev/sd[bcdjkl]1
.br
DEVICE /dev/hda1 /dev/hdb1
-# /dev/md0 is known by it's UID.
+# /dev/md0 is known by its UUID.
.br
ARRAY /dev/md0 UUID=3aaa0122:29827cfa:5331ad66:ca767371
.br
.br
ARRAY /dev/md1 superminor=1
.br
-# /dev/md2 is made from precisey these two devices
+# /dev/md2 is made from precisely these two devices
.br
ARRAY /dev/md2 devices=/dev/hda1,/dev/hdb1
projects / thirdparty / mdadm.git / blobdiff