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Index for Section 8 |
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Alphabetical listing for V |
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voldg(8)
NAME
voldg - Manage Logical Storage Manager (LSM) disk groups
SYNOPSIS
/sbin/voldg init groupname [medianame=]accessname...
/sbin/voldg [-fC] import diskgroup
/sbin/voldg deport diskgroup...
/sbin/voldg [-g diskgroup] [-k] adddisk [medianame=]accessname...
/sbin/voldg [-g diskgroup] [-k] rmdisk medianame...
/sbin/voldg [-q] list [diskgroup...]
/sbin/voldg [-g diskgroup] [-q] free [medianame...]
/sbin/voldg flush [diskgroup...]
DESCRIPTION
The voldg utility performs basic administrative operations on disk groups.
Operations include the creation of disk groups, the addition of disks to a
disk group, and disk group imports and deports. The behavior of the voldg
utility depends upon the keyword specified as the first operand.
A diskgroup argument can be either a disk group name or a disk group ID. A
groupname argument is a disk group name, not a disk group ID. An accessname
argument refers to a system-dependent disk access name (also referred to as
a disk device name), as stored in the root configuration by the voldisk
utility. A medianame argument is an administrative name defined within a
disk group.
An accessname argument names a disk access record (essentially a device
address specification) used to access the disk.
A medianame argument names the disk media record used to define the disk
within the disk group.
Supported operations include the following:
/sbin/voldg init
Define a new disk group composed of the indicated disks, identified by
disk access names. This involves assigning an internal unique ID to the
group, storing a pointer to that group in the root configuration,
storing a reference to the group on all of the named disks that have a
disk header, and storing a disk group record in the disk group's
configuration database. At least one of the disks specified must have
space allocated for a configuration copy.
If a medianame is specified for use with a particular disk, then that
medianame will name the disk media record used to reference the disk
within the disk group, for the rmdisk operation and for subdisk
creations. If no medianame is specified, then the disk media name
defaults to accessname. See voldisk(8) for discussion of definition and
initialization of disk access records for use with this operation.
The init operation can be used to initialize a root disk group
configuration, which is identified by the special name rootdg. If any
database locations are listed in the volboot file, then as a special
case for initializing rootdg, no disk specifications are allowed. Disks
should be initialized and added to the disk group as the first
operations after creating rootdg. Some or all disks added to the
rootdg disk group should also be added to the volboot bootstrap file
(see voldctl(8)).
/sbin/voldg import
Import a disk group to make the specified disk group available on the
local machine. This will make any configuration information stored with
the disk group accessible, including any disk and volume
configurations. The disk group to import is indicated by the diskgroup
argument, which can be either an administrative disk group name or a
disk group unique ID.
Normally, a disk group will not be imported if some disks in the disk
group cannot be found by the local host. The -f option can be used to
force an import if, for example, one of the disks is currently unusable
or inaccessible.
Note
Care must be taken when using the -f option, because it can cause
the same disk group to be imported twice from disjoint sets of
disks, causing the disk group to become inconsistent.
When a disk group is imported, all disks in the disk group are stamped
with the host's host ID. Normally, a disk group cannot be imported if
any of its disks are stamped with a non-matching host ID. This provides
a sanity check in cases where disks can be accessed from more than one
host.
If it is certain that a disk is not in use by another host (such as
because a disk group was not cleanly deported), then the -C option can
be used to clear the existing host ID on all disks in the disk group as
part of the import. A host ID can also be cleared using voldisk
clearimport.
Disk groups that have been imported will be reimported automatically
when the system is rebooted, if some or all disks in the disk group are
accessible and usable.
/sbin/voldg deport
Disable access to the specified disk group. A disk group cannot be
deported if any volumes in the disk group are currently open. When a
disk group is deported, the host ID stored on all disks in the disk
group will be cleared, so the disk group will not be reimported
automatically when the system is rebooted.
/sbin/voldg adddisk
Add additional disks to a disk group (rootdg by default). The disk must
not already be part of an imported disk group. The accessname
component to a disk specification argument names a disk access record
(essentially a device address specification) used to access the disk.
If a medianame component is specified, then it names the disk media
record used to define the disk within the disk group. If no medianame
component is specified, then the disk media record will have the same
name as the disk access record.
Adding a disk to a disk group causes the disk group's configuration to
be copied onto the disk (if the disk has regions for configuration
copies). Also, the disk is stamped with the system's host ID, as
defined in the volboot file.
If the -k option is specified, then the disk media name must represent
a disk media record that was previously dissociated from its disk
access record with -k rmdisk; otherwise, a new disk media record will
be created to represent the disk. With the -k option, plexes requiring
recovery will be flagged as stale.
/sbin/voldg rmdisk
Remove the specified disks from a disk group (rootdg by default). The
last disk cannot be removed from a disk group. It is not possible to
remove the last disk containing a valid disk group configuration or log
copy from its disk group.
Normally, the operation will fail if subdisk records point to the named
disk media records. However, if the -k option is specified, then the
disk media records will be kept, although in a removed state, and the
subdisk records will still point to them. The subdisks, and any plexes
that refer to them, will be unusable until the disk is re-added using
the -k option to the adddisk operation. Any volumes that become
unusable, because all plexes become unusable, will be disabled.
/sbin/voldg list
List the contents of disk groups. If no diskgroup arguments are
specified, then all disk groups are listed in an abbreviated one-line
format. If diskgroup arguments are specified, then a longer format is
used to indicate the status of the disk group, and of the disk group
configuration.
If the -q option is specified, then no header is printed describing
output fields. This option has no effect with the long formats
generated with diskgroup arguments.
/sbin/voldg free
List free space that can be used for allocating subdisks. If a disk
group is specified, limit the output to the indicated disk group,
otherwise list space from all disk groups. If disks are specified, by
disk media name, then restrict the output to the indicated disks. A
region of free space is identified by disk media name, a physical
device tag, an offset relative to the beginning of the public region
for the media, and a length.
The physical device tag is a reference that indicates which physical
device the disk media is defined on. It appears as a truncated disk
access name. If a particular physical device is split into several
Logical Storage Manager disk objects, then the device tag for each
Logical Storage Manager disk object will be the same. Device tags can
be compared to identify space that is on the same or on different
physical disks.
If the -q option is specified, then no header is printed describing
output fields.
/sbin/voldg flush
Rewrite all disk on-disk structures managed by the Logical Storage
Manager for the named disk groups. This rewrites all disk headers,
configuration copies, and kernel log copies. Also, if any configuration
copies were disabled, for example as a result of I/O failures, this
will rewrite those configuration copies and attempt to enable them.
SEE ALSO
volintro(8), vold(8), voldisk(8), volplex(8), volume(8)