.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
.br
DEV /dev/sd*
.br
-DEVICE /dev/discs/disc*/disc
+DEVICE /dev/disk/by-path/pci*
.br
DEVICE partitions
If no device name is given,
.I mdadm
will use various heuristics 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
match. Each identity word has a tag, and equals sign, and some value.
The tags are:
-
.RS 4
.TP
.B uuid=
.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
value given can be either a path name in /dev, or a UUID of the
container array.
-.IP
+.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.
+container the array is. It will usually accompany a "container=" word.
.RE
.TP
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.
+.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>
and
If
.B <ignore>
is given, then a flag is set so that when arrays are being
-auto-assemble the checking of the recorded
+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.
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 (possibly preceded by an underscore) to differentiate it
+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/home0 .
+.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
-preceded by plus or minus is allowed and is usually last.
+is usually last.
When
.I mdadm
-is auto-assembling an array, with via
-.I --assemble
+is auto-assembling an array, either via
+.I \-\-assemble
or
-.I --incremental
+.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
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.
+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
HOMEHOST <system>
.br
-AUTO +1.x -all
+AUTO +1.x homehost -all
.SH SEE ALSO
.BR mdadm (8),
projects / thirdparty / mdadm.git / blobdiff