Man page of volsd
Section: Maintenance Commands (8)
Return to Main Contents
volsd - Perform Logical Storage Manager (LSM) operations on subdisks
/sbin/volsd [-Vf] [-g diskgroup] [-U usetype] [-o useopt] [-v volume] [-l offset] assoc plex subdisk...
/sbin/volsd [-Vf] [-g diskgroup] [-U usetype] [-o useopt] [-v volume] aslog plex subdisk
/sbin/volsd [-Vf] [-g diskgroup] [-U usetype] [-o useopt] [-v volume] [-p plex] dis subdisk...
/sbin/volsd [-Vf] [-g diskgroup] [-U usetype] [-o useopt] [-v volume] [-p plex] split subdisk newsd [newsd2]
/sbin/volsd [-Vf] [-g diskgroup] [-U usetype] [-o useopt] [-v volume] [-p plex] join sd1 sd2... newsd
/sbin/volsd [-Vf] [-g diskgroup] [-U usetype] [-o useopt] [-v volume] [-p plex] mv oldsd newsd
The following options are recognized:
Specify the disk group for the operation, either by disk group
ID or by disk group name. By default, the disk group is chosen based on the
Limit the operation to apply to this usage type. Attempts
to affect volumes with a different usage type will fail.
Pass in usage-type-specific options to the operation. A certain
set of operations are expected to be implemented by all usage types:
Reduce the system performance impact of copy operations.
Copy operations are usually a set of short copy operations on small regions
of the volume (normally from 16 kilobytes to 128 kilobytes). This option
inserts a delay between the recovery of each such region. A specific delay
can be specified with
as a number of milliseconds,
or a default is chosen (normally 250 milliseconds).
Perform copy operations in regions with the length specified
size, which is a standard Logical Storage Manager
length number (see
volintro(8)). Specifying a larger number typically causes the operation
to complete sooner, but with greater impact on other processes using the volume.
The default I/O size is typically 32 kilobytes.
Remove the subdisks after successful completion of a
operation. Remove the source subdisk after successful
Write a list of utilities that would be called from
volsd, along with the arguments that would be passed. The
performs a ``mock run'' so the utilities are not actually called.
Specify the size for the subdisk
operation. This option takes a standard Logical Storage Manager length number
Specify the offset of a subdisk within a plex address space
operation. This option takes a standard
Logical Storage Manager length number (see
Require that a named plex be associated with this volume,
or that a named subdisk (source subdisk for
mv) be associated with a plex that
is associated with this volume.
Require that a named subdisk (source subdisk for
be associated with this plex.
Force an operation that the Logical Storage Manager considers
potentially dangerous or of questionable use. This permits a limited set
of operations that would otherwise be disallowed. Some operations may be
disallowed even with this flag.
utility performs Logical Storage Manager operations on subdisks
and on plex-and-subdisk combinations. The first operand is a keyword that
determines the specific operation to perform. The remaining operands specify
the configuration objects to which the operation is to be applied.
Each operation can be applied to only one disk group at a time, due
to internal implementation constraints. Any plex or subdisk name operands
will be used to determine a default disk group, according to the standard
disk group selection rules described in
volintro(8). A specific
disk group can be selected with
These are the recognized operation keywords:
Associate each named subdisk operand with the specified plex.
The offset within the plex for the association can be specified with
-l, which takes a standard Logical Storage Manager length number (see
If no offset is specified, then the default is to associate the subdisk at
the end of the plex, thus extending the length of the plex by the length of
the new subdisk.
A subdisk cannot be associated to overlap with an another associated
subdisk in the same plex. Subdisks associated with a striped plex must all
have the same length, and must be associated at offsets that are integral
multiples of the subdisk lengths. A striped plex associated with a volume
cannot be sparse: i.e., there can be no regions of blocks in the plex that
are not mapped to a subdisk.
If the named plex is associated with a volume, then the rules for performing
the operation depend upon the usage type of the volume. A subdisk cannot
be associated to a plex if the
field for the subdisk
is not empty. Creating a subdisk with the
set to a non-empty value is a sufficient means of ensuring that no Logical
Storage Manager operation will write to the region of disk blocks allocated
to the subdisk because the subdisk cannot be associated through any means
to a plex, and because subdisks cannot be used directly to read from or write
to a disk.
Associate the named subdisk with the named plex as a log area
for the plex. At most one log subdisk can be associated with a plex at any
one time. Log subdisks can be used only with the block change logging feature,
as defined by the
volume logging type. If the named
plex is associated with a volume, then the rules for performing the operation
depend upon the usage type of the volume. A subdisk cannot be associated
field is set on the subdisk, just as with
Dissociate each specified subdisk from the plex that it is
associated with. Subdisks cannot be dissociated from striped plexes. If
a subdisk is associated (through its plex) with a volume, then the rules for
performing the operation depend upon the usage type of the volume.
Subdisk dissociation can be used as part of tearing down a plex, or
as part of reorganization of disk space usage. Typically, the subdisk is
no longer needed after dissociation. To support this type of use,
can be specified to remove the named subdisks after
Split the subdisk
two subdisks that reside on the same section of the same device, and that
have contiguous plex associations (if the named subdisk is associated). The
first of the two resultant subdisks will have a length of
size, and the second will take up the remainder of the space used
by the original subdisk. If both
are specified, then the resultant subdisks are
newsd2. If no
operand was specified, then the resultant subdisks are
If the named subdisk is associated with an associated plex, then the
rules for performing the operation depend upon the usage type of the volume.
Log subdisks and subdisks associated with striped plexes cannot be split.
Join the subdisks named by the
operands to form a new subdisk named
operands must specify subdisks that represent contiguous
sections of the same device, and of the same plex (if they are associated).
At least two
operands are required. At the
end of the operation, the
are removed. The
operand can have the same
name as one of the
operands, or it can have
a different name.
operands are associated with an
associated plex, then the rules for performing the operation depend upon the
usage type of the volume. Subdisks associated with a striped plex cannot
Move the contents of
for any associations. The operation requires that
be associated with an associated plex and that
be dissociated. The operation can be used on a subdisk
that is used by an active volume, and will ensure that data is copied and
associations are changed without loss or corruption of data. Subdisks associated
with striped plexes cannot be moved. The rules for performing the operation
depend upon the usage type of the volume.
Moving a subdisk is the normal means of reorganizing disk space. For
example, move regions of disk used by one volume to another disk to reduce
contention on the original disk. Typically, once the operation completes,
the original subdisk is no longer needed and can be removed. To support this
use of the operation,
can be specified
after successful completion of
FSGEN AND GEN USAGE-TYPES
provide identical semantics for all operations of the
operation is interrupted by a signal,
then an attempt is made to restore the disk group configuration to a state
that is roughly equivalent to its original state. If this attempt is interrupted,
such as through another signal, then the user may need to perform some cleanup.
The specific cleanup actions that are needed are written to the standard
In addition to the standard
options required for
all usage types, the
types provide the following additional option:
Force an operation that the Logical Storage Manager considers
potentially dangerous or of questionable use. This applies to attempts to
dissociate subdisks (making a plex sparse) and to attempts to move subdisks
onto subdisks that have a different size. This flag is the same as
Limitations and extensions for the
usage types consist of the following:
If the named plex is enabled, and is associated with an enabled
plex, then the named plex must
EMPTY. Subdisks can be associated with a non-enabled plex only if the
utility state of the plex is
OFFLINE, or if the plex is
and no other plexes associated with the volume are
If the subdisk is associated with a non-enabled plex, or if it is associated
with the only enabled, read-write plex in a volume, then the operation completes
without copying any data onto the subdisk. If the subdisk is associated with
an enabled plex in a mirrored volume, then the operation may have to copy
data from the volume onto the new subdisk before the operation can complete.
If a log subdisk is associated with a plex that is associated
with a volume that has a logging type of
UNDEF, then the
logging type of the volume is converted to
of volume changes is not enabled until two or more attached plexes have associated
Dissociating a subdisk requires use of
if it would cause an enabled plex in an enabled volume to become sparse relative
to the volume. Even with
-f, it is not possible to make two
plexes sparse if no complete, enabled, read-write plexes would remain associated.
For disabled volumes, a similar check is made with respect to
types apply no additional restrictions and add no extensions to the
If the size of the destination subdisk differs from that of
the source subdisk, then the
option must be specified.
The operation still fails if the destination subdisk is larger than the source
subdisk and if the address range of the destination would conflict with another
subdisk that is associated with the plex. The destination subdisk cannot
be larger than the source subdisk if the kernel state of the volume or plex
The operation fails if the destination subdisk is smaller than the source
subdisk and the operation would cause the total number of complete, enabled,
read-mode plexes in the volume to drop to zero, while leaving more than one
sparse, enabled, read-write plex.
utility exits with a nonzero status if
the attempted operation fails. A nonzero exit code is not a complete indicator
of the problems encountered, but rather denotes the first condition that prevented
further execution of the utility. See
for a list of
standard exit codes.
The utility that performs
for a particular volume usage type.
- FSGEN AND GEN USAGE-TYPES
- EXIT CODES
- SEE ALSO
This document was created by
using the manual pages.
Time: 02:40:33 GMT, October 02, 2010