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 .
.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>
.B HOMEHOST
line.
+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
.TP
.B POLICY
-Allows 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 array as well as the migration domains.
+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. Domain of an array is a union
-of domains of all devices in that array. A spare can be automatically
+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
+ppcontains 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 config file
+command after changing the config file
-Key words used in
+Key words used in the
.I POLICY
-line and supported values:
+line and supported values are:
.RS 7
.TP
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
+.B auto=
+yes, no, or homehost.
.P
The
.I action
item determines the automatic behavior allowed for devices matching the
.I path
-in the same line. If a device matches several lines with different
+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.
allows adding a disk to an array if metadata on that disk matches that array
.TP
.B re-add
-will include device in the array if it appears to be a current member
+will include the device in the array if it appears to be a current member
or a member that was recently removed
.TP
.B spare
-as above and additionally: if the device is bare it will
-become a spare (for metadata the same line)
+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
.br
HOMEHOST <system>
.br
-AUTO +1.x homehost -all
+AUTO +1.x homehost \-all
.SH SEE ALSO
.BR mdadm (8),
projects / thirdparty / mdadm.git / blobdiff