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.
Alternatively, a
.B device
-line can contain either of both of the words
+line can contain either or both of the words
.B containers
and
.BR partitions .
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
+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
+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"
.B \-\-scan
option). There should only be one
.B MAILADDR
-line and it should have only one address.
-
+line and it should have only one address. Any subsequent addresses
+are silently ignored.
.TP
.B MAILFROM
.B CREATE
The
.B create
-line gives default values to be used when creating arrays and device entries for
-arrays.
+line gives default values to be used when creating arrays, new members
+of arrays, and device entries for arrays.
These include:
.RS 4
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=
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
-.B <system>
+.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.
+systemcall is used to get the host name. This is the default.
If
.B <ignore>
used when creating arrays. This is the only case when there can be
more that one other word on the
.B HOMEHOST
-line.
+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
.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
+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
.B path=
file glob matching anything from
.B /dev/disk/by-path
+.TP
.B type=
-either
+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
.B include
allows adding a disk to an array if metadata on that disk matches that array
.TP
-.B re-add
+.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
+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
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
+.B force\-spare
as above and the disk will become a spare in remaining cases
.RE
.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
HOMEHOST <system>
.br
-AUTO +1.x homehost -all
+AUTO +1.x homehost \-all
.SH SEE ALSO
.BR mdadm (8),
.BR md (4).
-