MDADM.CONF(5)							File Formats Manual						     MDADM.CONF(5)

NAME

       mdadm.conf - configuration for management of Software Raid with mdadm

SYNOPSIS

       /etc/mdadm.conf

DESCRIPTION

       mdadm is a tool for creating, managing, and monitoring RAID devices using the md driver in Linux.

       Some common tasks, such as assembling all arrays, can be simplified by describing the devices and arrays in this configuration file.

   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.

       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:

       DEVICE A  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, mdadm will scan these devices (or any devices listed on the command line).

	      The device line may contain a number of different devices (separated by spaces) and each device  name  can  contain  wild  cards	as
	      defined by glob(7).

	      Also, there may be several device lines present in the file.

	      For example:

	      DEVICE /dev/hda* /dev/hdc*
	      DEV    /dev/sd*
	      DEVICE /dev/discs/disc*/disc

       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
	      assembled, such as /dev/md1.  Subsequent words identify the array, or identify the array as a member of a group. If multiple identi-
	      ties  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:

	   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.

	   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.

	   devices=
		  The value is a comma separated list of device names. Precisely these devices will be used to assemble the array.  Note that  the
		  devices listed there must also be listed on a DEVICE line.

	   level= The value is a raid level.  This is not normally used to identify an array, but is supported so that the output of

		  mdadm --examine --scan

		  can be use directly in the configuration file.

	   num-devices=
		  The  value is the number of devices in a complete active array.  As with level= this is mainly for compatibility with the output
		  of

		  mdadm --examine --scan.

	   spare-group=
		  The value is a textual name for a group of arrays.  All arrays with the same spare-group name are considered to be part  of  the
		  same	group.	 The significance of a group of arrays is that 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.

       MAILADDR
	      The mailaddr line gives an E-mail address that alerts should be sent to when is running in --monitor mode (and was given the  --scan
	      option).	There should only be one MAILADDR line and it should have only one address.

       PROGRAM
	      The  program  line  gives  the name of a program to be run when 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 program line and it should be give only one program.

EXAMPLE

       DEVICE /dev/sd[bcdjkl]1
       DEVICE /dev/hda1 /dev/hdb1

       # /dev/md0 is known by it's UID.
       ARRAY /dev/md0 UUID=3aaa0122:29827cfa:5331ad66:ca767371
       # /dev/md1 contains all devices with a minor number of
       #   1 in the superblock.
       ARRAY /dev/md1 superminor=1
       # /dev/md2 is made from precisey these two devices
       ARRAY /dev/md2 devices=/dev/hda1,/dev/hda2

       # /dev/md4 and /dev/md5 are a spare-group and spares
       #  can be moved between them
       ARRAY /dev/md4 uuid=b23f3c6d:aec43a9f:fd65db85:369432df
		  spare-group=group1
       ARRAY /dev/md5 uuid=19464854:03f71b1b:e0df2edd:246cc977
		  spare-group=group1

       MAILADDR root@mydomain.tld
       PROGRAM /usr/sbin/handle-mdadm-events

SEE ALSO

       mdadm(8), md(4).

																     MDADM.CONF(5)