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volassist - Create, mirror, back up, grow, shrink, move, add logs to, and
support online backup of LSM volumes
/sbin/volassist help [help_topic | showattrs | space]
/sbin/volassist [-g diskgroup] [-U usetype] [-o useopt] [-b] [-c nocluster]
make volume length [attribute...]
/sbin/volassist [-g diskgroup] [-U usetype] [-o useopt] [-b] mirror volume
/sbin/volassist [-g diskgroup] [-U usetype] [-o useopt] [-c nocluster]
addlog volume [attribute...]
/sbin/volassist [-g diskgroup] [-U usetype] [-o useopt] [-c nocluster]
addfpa volume [attribute...]
/sbin/volassist [-g diskgroup] [-U usetype] [-o useopt] [-b] move volume
/sbin/volassist [-g diskgroup] [-U usetype] [-o useopt] [-b] growto volume
/sbin/volassist [-g diskgroup] [-U usetype] [-o useopt] [-b] growby volume
/sbin/volassist [-g diskgroup] [-U usetype] [-o useopt] shrinkto volume
/sbin/volassist [-g diskgroup] [-U usetype] [-o useopt] shrinkby volume
/sbin/volassist [-g diskgroup] [-U usetype] [-o useopt] snapfast
/sbin/volassist [-g diskgroup] [-U usetype] [-o useopt] snapback
/sbin/volassist [-g diskgroup] [-U usetype] [-o useopt] [-b] snapstart
/sbin/volassist [-g diskgroup] [-U usetype] [-o useopt] snapshot volume
/sbin/volassist [-g diskgroup] [-U usetype] [-o useopt] snapwait volume
/sbin/volassist [-g diskgroup] [-U usetype] [-o useopt] [-p] maxsize
/sbin/volassist [-g diskgroup] [-U usetype] [-o useopt] [-p] maxgrow volume
Specifies 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
storage specification attributes (if any) for the volassist make
operation, or based on the volume operands for all other operations.
Limits the operation to apply to this usage type. Attempts to affect
volumes with a different usage type will fail. For a volassist make
operation, this indicates the usage type to use for the created volume.
Otherwise, the default is used and is determined by the existence of an
entry in the /etc/default/volassist file or is set to the fsgen usage
Passes in usage-type-specific options to the operation. A certain set
of operations are expected to be implemented by all usage types:
Reduces the system performance impact of copy operations. Copy and
plex consistency recovery operations are usually a set of short
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 iodelay as a number of milliseconds, or a default is chosen
(normally 250 milliseconds).
Performs copy and recovery operations in regions with the length
specified by 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 between 32 and 256 kilobytes.
-b Performs extended operations in the background. This applies to plex
consistency recovery operations for volassist make, growto, and growby.
This flag also applies to plex attach operations started by volassist
mirror and volassist snapstart but not to the snapback operation.
Specifies a file containing defaults for various attributes related to
volume creation and space allocation. Attribute values that are passed
in through this file will override any values specified in the system
defaults file, /etc/default/volassist.
-f Forces certain operations that are disallowed by default to prevent
their incorrect use. The force option is required to:
· Shrink a volume (with shrinkto or shrinkby).
· Create a RAID 5 volume using the nolog attribute.
· Grow a primary volume that is actively FPA logging (while a
migrant plex is attached to a secondary volume). Use this option
with caution, as it disables the FPA log plex on the primary
volume, resulting in a full plex resynchronization when the
migrant plex is reattached to the primary volume.
Specifies a log size (for a DRL or FPA log plex) for mirrored volumes
of 2 blocks per GB of volume size, instead of 65 blocks per GB (the
default). Applicable only on a standalone system. This option is
disabled in a TruCluster Server environment. If the volume is later
imported on a cluster, logging is disabled for the volume.
-p Limits the output of the maxsize and maxgrow operations to a numeric
value only (no text). This option is mainly for use in scripts.
-n Prevents volassist from using the defaults specified in the system
defaults file, /etc/default/volassist, when creating volumes.
-v Specifies verbose mode, printing a trace of other utilities that are
The volassist command is an LSM command that finds space for and creates
volumes, adds mirrors and logs to existing volumes, extends and shrinks
existing volumes, provides for the migration of data from specified disks,
and provides facilities for the online backup of existing volumes.
volassist operations are applied to only one disk group at a time, which by
default is the rootdg disk group. Use the -g diskgroup option to specify a
disk group. You can specify a default disk group in the
Many volassist operations use attributes to specify how volumes are laid
out and on which disks, among other things. Attributes are of two basic
types: storage specifications and attribute settings.
Storage specification attributes consist of a simple disk media name (for
example, disk01) or disk access name (for example, dsk5a). If the storage
specification attribute is prefixed with ! (or, \! from csh), the specified
disk or partition is excluded from the operation. For example, the
following command creates a 1000MB volume on any nonvolatile, unreserved
disk other than disk03:
/sbin/volassist make vol1 1000m !disk03
Other attributes are of the form attrname=value. These attributes specify
the type of a volume (mirrored, RAID 5, striped, logged), layout policies
(contiguous, spanning), mirroring requirements and more. See KEYWORDS for a
complete list of attribute specifications.
volassist keywords are:
Displays a list of help topic keywords that can be combined with
volassist help to display detailed information on command usage,
options, and attributes.
The volassist help showattrs keyword combination displays a list of
current attribute settings.
The volassist help space keyword combination displays current disk
Creates a volume with the specified name and the specified length. The
length is specified as a standard Logical Storage Manager length (see
volintro(8)). Attributes can be specified to indicate various desired
properties and storage locations for the created volume.
By default, a DRL is created when you create a mirrored volume and a
RAID 5 log is created when you create a RAID 5 volume. Use the
layout=mirror,nolog option to create a mirrored volume with DRL
disabled. See EXAMPLES.
Creates a new mirror (plex) and attaches it to a concatenated or
striped volume. This operation is allowed only if the volume is
enabled. You can specify attributes to indicate desired properties and
storage locations for the mirror. A mirrored volume has at least two
data plexes. When mirroring a previously unmirrored volume, LSM does
not add a DRL. Use volassist addlog to add a log.
Adds a log to a RAID 5 volume or to a mirrored volume whose logging
type is DRL (the default). Adding a log to a mirrored volume involves
creating a single log subdisk and a new plex to contain that subdisk.
The new plex is then attached to the volume. Adding a log to a RAID 5
volume involves creating a new plex that attaches to the volume as a
log plex. The addlog command automatically creates and attaches these
Adding a DRL log to the root volume (rootvol) on a standalone
system, the cluster root domain volume (clurootvol) in a cluster, or
any swap volume is unsupported.
When adding the first log to a mirrored or RAID 5 volume, you can use
the loglen=length attribute to specify the length of the log.
Otherwise, LSM uses the default log size, which LSM calculates based on
the volume size and layout type.
Subsequent logs added to the volume use the loglen attribute of the
first log. You can specify other attributes to indicate desired
properties for the new allocations. Mirroring constraints do not apply
to logs, though storage constraints can be specified that constrain the
logs to disks already used by the volume. However, for better
performance, the DRL should not use disks that are currently used for
volume data. See EXAMPLES.
The minimum DRL length is 65 blocks for a cluster environment, and 2
blocks for a non-cluster environment. By default, LSM configures a
larger log subdisk for the DRL than needed. This allows you to use the
volume if the system becomes a Tru64 UNIX cluster member. If you
configure a DRL size less than 65 blocks for a non-cluster environment,
DRL is disabled for that volume if you later migrate it to a cluster
Creates and attaches an FPA log to the specified volume. If the volume
has a DRL log, the FPA log length will be the same as the DRL. If not,
when adding the first FPA log to a mirrored volume, you can specify the
length of the log with the loglen=length attribute, the number of FPA
logs with the nfpalog=count attribute, and which disks it can or cannot
use. To exclude storage, use the ! prefix (or \! in csh).
If the volume already has one FPA log you can add another for
redundancy, just as for DRL logs, except while a migrant plex is
detached from the volume (attached to a secondary volume).
Adding an FPA log is supported for the root volume (rootvol) on a
standalone system and the cluster root domain volume (clurootvol) in a
cluster, but not for swap volumes.
Moves subdisks within the named volume off the excluded storage
specified on the command line. Excluded storage is specified with a
prefix of ! (or, \! from csh). The move operation requires that at
least one excluded storage specification be given. See Storage
Specifications for a description of how to specify the excluded
You can specify a target device for the move or allow LSM to use any
available space in the disk group. If you specify a target device it
must be large enough to support the move (equal to or larger than the
excluded storage) or the move will fail.
If the volume is enabled, subdisks within detached or disabled plexes
(or detached log or RAID 5 subdisks) will be moved without recovery of
data. If the volume is not enabled, stale log or RAID 5 subdisks, or
subdisks within STALE or OFFLINE plexes, will be moved without
recovery. If there are other subdisks within a non-enabled volume that
require moving, the move operation will fail.
For enabled subdisks in enabled plexes within an enabled volume, the
data within subdisks will be moved to the new location, without loss of
availability (or redundancy) of the volume.
growto and growby
Increases the length of the named volume to the length specified by
new_length (growto), or by the length specified by length_change
(growby). The new length or change in length is specified as a standard
Logical Storage Manager length (see volintro(8)). The growto operation
fails if the new length is not greater than the current volume length.
The length of the volume is increased by extending existing subdisks in
the volume, or by adding and associating new subdisks. Plexes that are
not fully populated already (that is, that are sparse) are left
unchanged. Log-only plexes are also left unchanged.
Attributes can be specified to indicate various desired properties for
the new allocations. Any mirroring constraints will still apply between
all extensions to the existing mirrors and the other mirrors.
Growing a volume requires that the volume be enabled. Growing a volume
that is actively FPA logging (a migrant plex is detached) requires the
The volassist growto/growby operations have no effect on any file
systems that reside on the volume (or other users of the volume). It is
expected that any necessary application notifications will be made
after the grow operation completes successfully.
shrinkto and shrinkby
Decreases the length of the named volume to the length specified by
new_length (shrinkto), or by the length specified by length_change
(shrinkby). The new length or change in length is specified as a
standard Logical Storage Manager length (see volintro(8)). The shrinkto
operation fails if the new length is not less than the current volume
The length of a volume is decreased by removing and shortening subdisks
to leave each plex with the desired volume length. The freed space can
then be allocated for use by other volumes. Log-only plexes are left
The volassist shrinkto/shrinkby operations have no effect on any file
systems that reside on the volume (or other users of the volume). It is
expected that any necessary application notifications will be made
before the shrink operation is initiated.
File systems such as AdvFS and UFS cannot currently take advantage
of a shrunk volume.
These operations are currently disallowed by default to prevent
their incorrect use with an existing AdvFS or UFS file system. To
override this default behavior and force the volume to shrink, you
must use the -f force option.
Creates and adds an FPA log plex to the specified volume (if none
exists), adds an FPA logging subdisk to an active data plex,
synchronizes both FPA logs, detaches the plex with the FPA subdisk (now
considered a migrant plex) from the volume (now considered the primary
volume), creates a secondary volume with the specified name and
attaches the migrant plex to the secondary volume.
Only one snapfast operation at a time is permitted on a volume. After a
migrant plex is returned to the primary volume and fully resynchronized
(with the snapback command), another snapfast operation can be
There is no limit to how long a migrant plex can be detached from its
primary volume; however, the benefit of using FPA might be reduced as
more writes occur to either volume.
Detaches a migrant plex from the specified secondary volume, reattaches
the migrant plex to the primary volume, merges the FPA logs for the
primary volume and the migrant plex, and manages atomic copies to
resynchronize the migrant plex to the primary volume. The FPA subdisk
attached to the migrant plex is disabled and destroyed, and the disk
space it used is returned to the free space pool until the next
If the secondary volume had only one plex (the migrant plex), the
secondary volume is destroyed.
snapstart and snapshot
Creates a temporary mirror and attaches it to the named volume. When
the attach completes, the mirror will be considered a candidate for
selection by the snapshot operation. The snapshot operation takes one
of these attached temporary mirrors and creates a new volume with the
temporary mirror as its one plex. You can specify attributes to
indicate desired properties of the snapshot mirror.
Some usage types will attempt to synchronize any in-memory data
associated with the volume (such as unwritten file system
modifications) when the snapshot operation is done. For UFS, the
synchronization operation consists of a call to sync(8), which will
make the snapshot a better image, but which may leave some
inconsistencies between in-memory file system data and the data
residing on the backup image.
To ensure data synchronization with AdvFS file systems, you must
unmount the file systems before doing the snapshot operation.
If a snapstart mirror attach is done as a background task (such as
using the -b option), it may be convenient to wait for an attached
mirror to become available. The snapwait operation waits for such an
attach to complete on the named volume. When a snapshot attach has
completed, the operation exits.
Returns information on the maximum volume size that can be created from
the available space, given a particular set of attributes. See
EXAMPLES. When used with the -p option, maxsize returns a numeric
Returns information on the maximum amount of space by which the
specified volume can be extended and the maximum size to which it can
grow, given the available space and a particular set of attributes.
When used with the -p option, maxgrow returns a numeric value only,
indicating the maximum size to which the volume can grow.
You can specify values for various attributes with arguments of the form
attribute=value, or as a list of (possibly negated) storage specifications.
Attributes can also be passed in through a defaults file. Default attribute
values can be stored in the file /etc/default/volassist. In a defaults
file, attributes are separated by spaces or are on separate lines. Blank
lines in a defaults file are ignored, and comments can be included with the
standard # convention.
Attributes are applied according to the order in which they are scanned.
If conflicting attributes are specified, the last one specified takes
precedence and is used. In general, attributes are applied, in decreasing
1. The command line.
2. The specified defaults file, as supplied with the -d command line
3. The system defaults file, as specified in /etc/default/volassist.
Attributes from all sources have the same form. However, in some cases,
command-line attributes change default behaviors in ways that defaults-file
supplied attributes do not. In particular, references to mirroring (such as
specifying a mirror count) or logging (such as specifying a log count or
length) on the command line will cause mirroring or logging to happen by
default. If such attributes are specified in a defaults file, they just
indicate the attributes that would be used if mirroring or logging were
Storage specification attributes have one of the following forms:
Specifies (or excludes) the given disk. The diskname parameter refers
to a disk media record name in a Logical Storage Manager disk group.
Specifies (or excludes) a specific Logical Storage Manager disk by disk
access record name. An example of a disk access record name is dsk5a,
which indicates a special Logical Storage Manager disk defined on
partition a of disk dsk5.
[!]device:dev_name (alias d)
Specifies (or excludes) all LSM disks on a specific physical disk. The
physical disk is specified in the form dsk#, which indicates the disk
number. Normally, only one LSM disk device is created for each physical
disk. However, the voldisk define operation (see voldisk(8)) can be
used to create additional LSM disk devices on selected partitions.
[!]dm:dm_name (alias disk)
Specifies (or excludes) a Logical Storage Manager disk by disk media
record name, in the disk group of the volume.
Other attributes are of the form attribute=value. The attribute name in an
attribute value pair will never contain a colon, so it is possible to
specify a disk that has an equal sign in its name using the storage
specification dm:disk01=a. Without the dm: prefix, disk01=a would yield an
error indicating an unrecognized attribute.
Defined attributes (and common aliases) are:
This is provided as an alternate syntax for specifying storage as
single attributes. It is useful in a defaults file, so that all
attributes (including storage specifications) will be in the
attribute=value format. Any number of storage specifications can be
specified, separated by commas. More than one alloc attribute can be
specified, in which case they are logically concatenated to form one
Specifies a comment to give to a volume when it is created. This
comment can be displayed with volprint -l, and can be changed, at a
later time, with voledit set. This attribute is used only with the make
diskgroup=diskgroup (alias: dg)
Specifies the disk group for an operation. If a disk group is
specified in a defaults file, it just specifies the default disk group
to use for the make operation, if no other means of determining the
disk group can be used. If specified as a command line attribute, it
has the same effect as specifying a disk group with the -g option (the
operation is forced to apply to the given disk group).
Sets the owning group for a new volume. The group can be specified
numerically or with a system group name. This attribute is used only
with the make operation. By default, volumes are created in group 0.
Specifies the means for initializing a new volume. The default method
(which can be selected explicitly with init=default) is to call volume
start to do a usage-type-specific default initialization operation.
Some useful initialization states for new volumes include:
· init=none, which leaves the volume uninitialized.
· init=zero, which clears (zeroes out) the volume before it is
· init=active, which indicates that the plexes of a mirrored volume
do not need an initial synchronization. This can save time prior
to creating a file system when the contents of the volume are
guaranteed to be written before being read.
Specifies a volume or plex layout type (concatenated, RAID 5, mirrored,
unmirrored, striped, and others) and turns on or off some features
(such as logging). By default, LSM creates an unmirrored, non-striped
(concatenated) volume with no log.
See the next section (Layout Specifications) for the defined
Specifies a log length to use for dirty region log subdisks for
mirrored volumes, FPA log plexes or subdisks for the Fast Plex Attach
feature, or for RAID 5 log plexes. If a log length is specified on the
command line, logging is enabled by default.
Specifies the logging type for a mirrored volume. Dirty region logging
(the default) can be selected with either logtype=drl or
logtype=region. To disable logging, enter: logtype=none.
max_nraid5column=number (alias: maxraid5columns)
Specifies the default maximum number of stripe columns for a RAID 5
volume (default value: 8).
max_ncolumn=number (alias: maxcolumns)
Specifies the default maximum number of stripe columns, either for a
RAID 5 volume (if max_nraid5stripe is omitted) or for a striped plex
(default value: 8).
max_regionloglen=length (alias: maxregionloglen)
Specifies the maximum default dirty region log (DRL) subdisk length. If
you do not specify the DRL length for a volume, when creating the first
log for a mirrored volume, volassist uses a simple formula based on the
log length. The default length will not be overridden by
max_regionloglen (default value: 32K).
min_nraid5column=number (alias: minraid5columns)
Specifies the minimum number of stripe columns for a RAID 5 volume. The
default is 3 columns. The policy for selecting a default number of RAID
5 stripe columns is not to allow a RAID 5 volume to have fewer than
min_nraid5stripe stripe columns. The minimum number of columns that you
can have is 3.
min_nstripe=number (alias: minstripes)
Specifies the default minimum number of stripe columns for either a
RAID 5 volume (if min_nraid5stripe is omitted) or for a striped plex
(default value: 2). The policy for selecting a default number of stripe
columns is not to allow fewer than this number of columns.
Specifies mirroring parameters. A decimal number indicates a specific
number of mirrors to create, when creating a mirrored volume
(equivalent to nmirror=number). A value of yes indicates that volumes
should be mirrored by default (equivalent to layout=mirror). A value of
no indicates that volumes should be unmirrored by default (equivalent
Specifies the permissions for the block and character device nodes
created for a new volume. The mode can be specified either as an octal
number or symbolically. A symbolic mode is specified using the syntax
given in chmod(1). This attribute is used only with the make operation.
The default mode for a volume gives read and write access only to the
Specifies the number of logs to create, by default, for a RAID 5 or
mirrored volume (presuming that logs will be created). The number of
logs to create can be specified independently for RAID 5 or mirrored
volumes using the nraid5log and nregionlog attributes, respectively.
Specifies the number of mirrors to create when mirroring a volume
(default value: 2).
Specifies the number of log plexes to create for a new RAID 5 volume
(default value: 1). This attribute is used only with the make
nraid5stripe=number (alias: raid5stripes)
Specifies the number of stripe columns to use when creating a new RAID
5 volume (the default is to adjust the number to available disks). This
attribute is used only with the make operation.
Specifies the number of log subdisks to create for a new mirrored
volume (default value: 1). This attribute is used only with the make
operation, and only if logging is requested for the volume.
Specifies the number of FPA logs to create and attach to a volume
(default value: same as the value of nlog, if set).
nstripe=number (alias: stripes, ncolumn)
Specifies the number of stripe columns to use when creating a new RAID
5 volume (with the make operation) or when creating a striped plex
(with the make, mirror, and snapstart operations). The default is half
of the candidate disks, adjusted to a number between 2 and 8.
raid5_stripeunit=width (alias: raid5_stwidth)
Specifies the stripe unit size to use when creating a new RAID 5 volume
(default value: 16K). This attribute is used only with the make
Specifies the log length to use when adding the first log to a RAID 5
volume. The default is ten times the full stripe width (the stripe unit
size times the number of stripe columns).
Specifies the log subdisk length to use when adding the first log
subdisk to a mirrored volume. The default is based on a formula
involving the volume length.
stripe_stripeunit=width (alias: stripe_stwidth)
Specifies the stripe unit size to use when creating striped plexes to
attach to a volume. When attaching a new plex, the default is to use
the same stripe unit size as any other striped plexes in the volume. If
the volume does not yet contain striped plexes, the default value is
stripeunit=width (alias: stwidth, stripewidth)
Specifies the stripe unit size to use for either a RAID 5 volume or for
striped plexes. This attribute can be used to set the values for both
raid5_stripeunit and stripe_stripeunit.
Specifies the owning user for a new volume (default value: root). The
user can be specified numerically or it can be a system login name.
This attribute is used only with the make operation.
Specifies the usage type to use when creating a new volume with the
make operation (default value: raid5 for RAID 5 volumes; fsgen
otherwise). The usage type can also be specified in the option list
Specifies a set of desired storage specifications. This is useful in a
defaults file to indicate desired storage specifications that should be
discarded if they fail to yield a reasonable set of allocations. The
format is the same as for the alloc attribute (a comma-separated list
of storage specifications).
The layout attribute specifies a comma-separated list of parameters (with
no arguments) that define how the volassist command creates a volume.
Layout specifications are:
Specifies whether or not the volumes should use concatenated plexes.
This is the default.
mirror, nomirror, raid5
Specifies whether or not the volume uses mirrored plexes or RAID 5
plexes. The default is to create the volume without mirror or RAID 5
When creating a new volume or adding a plex to a volume that does not
have a striped plex, the default is nostripe. When adding a new plex to
a volume that has a striped plex, the default is stripe.
Allows (default) or disallows plexes, stripe columns, or RAID 5 stripe
columns to span multiple disks. If nospan is indicated, plexes or
columns can be formed from multiple regions of the same disk, but
cannot be formed from more than one disk.
Disallows or allows (default) plexes, stripe columns, or RAID 5 stripe
columns to use multiple regions of disk. If contig is specified, plexes
and columns must be allocated from a single contiguous region of disk.
If this is not possible, the allocation fails. By default, the
volassist command tries to allocate space contiguously, but will use
multiple regions or multiple disks if needed.
Creates (default) or doesn't create a DRL or RAID 5 log plex. You can
specify this attribute independently for volumes that use mirrored and
RAID 5 plexes by using the raid5log and regionlog layout
specifications. You must use the -f option to create a volume that uses
a RAID 5 plex with the nolog attribute.
Creates (default) or doesn't create log plexes for volumes that use a
RAID 5 plex. The -f option must be used with noraid5log to override the
Creates (default) or doesn't create a DRL for volumes that use mirror
fpa Creates an FPA log for volumes that use mirror plexes.
The volassist command 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 command.
See volintro(8) for a list of standard exit codes.
Create a mirrored, concatenated 600 MB volume using disks dsk6 and dsk7 in
disk group dg1:
# volassist -g dg1 -U gen make newvol 600m nmirror=2 init=active dsk6 dsk7
Exclude a disk from being used in a new volume:
# volassist make volA 4g nstripe=4 nmirror=2 !dsk8
Create a RAID 5 volume striped over five columns:
# volassist make bigvol 3g layout=raid5 ncolumn=5
Create a mirrored volume with DRL disabled:
# volassist make vol1 1g layout=mirror,nolog
Add a mirror to a volume:
# volassist mirror myvol
Add a mirror to a volume, specifying which disks to use for the mirror:
# volassist -g dg1 mirror bigvol layout=stripe ncolumn=4 dsk6 dsk7 dsk8 dsk9
Add a log to a mirrored or RAID 5 volume, specifying which disk to use for
# volassist -g dg1 addlog volB dsk10
Enable FPA logging on a volume:
# volassist addfpa vol09 loglen=65 nfpalog=2 dsk11 dsk12
Use the fast plex attach feature to create a secondary (backup) volume:
# volassist snapfast vol09 vol09_Monday_backup
Reattach the migrant plex to the primary volume and remove the secondary
# volassist snapback vol09_Monday_backup vol09
Determine the largest striped, three-way mirrored, four-column volume that
you can make in the dg2 disk group, excluding dsk8:
# volassist -g dg2 maxsize layout=stripe ncolumn=4 nmirror=3 !dsk8
System default settings file for volassist attributes. This is an
optional, user-created file that resides in the /etc/default directory,
which is also user-created.
Commands: voledit(8), volmake(8), volmend(8), volplex(8), volsd(8),
listing for V