addvol(8)addvol(8)NAMEaddvol - Adds a volume to an existing domain
SYNOPSIS
/usr/sbin/addvol [-F] [-x num_pages] [-p num_pages] special domain
OPTIONS
Ignores overlapping partition or block warnings. Sets the number of
pages to preallocate for the bitfile metadata table (BMT). The default
is 0 (zero) pages. This option may be useful if you are adding volumes
to domains that were created prior to the release of Version 5.0, or
with the -V3 option of the mkfdmn command. Sets the number of pages by
which the bitfile metadata table (BMT) extent size grows. The value
must be greater than or equal to 128 pages. The default is 128 pages.
This option may be useful if you are adding volumes to domains that
were created prior to the release of Version 5.0, or with the -V3
option of the mkfdmn command.
OPERANDS
Specifies the block device special device name, such as
/dev/disk/dsk1c, or the LSM volume name of the disk that you are adding
to the domain. This command supports shorthand device names for block
special devices. For example, if you enter dsk2g, it will be translated
to /dev/disk/dsk2g. Specifies the name of the AdvFS domain.
DESCRIPTION
A newly created domain consists of one volume which can be a disk or a
logical volume. The addvol utility enables you to grow the number of
volumes within an existing domain. You can add volumes immediately
after creating a domain, or you can wait until the filesets within the
domain require additional space.
For optimum performance, each volume that you add should consist of the
entire disk (typically, partition c). Existing data on the volume you
add is destroyed during the addvol procedure.
Caution
Do not add a volume containing data that you want to keep.
The addvol command checks for potential overlapping partitions before
adding the volume. A partition overlap would occur if you tried to add
a volume to a domain when a partition in it is already in use by a file
system, such as AdvFS or UFS; a storage manager, such as LSM or a raw
database; or a swap area. The overlap partition check prevents this
error from occurring. The check is performed on partitions that are
active (open) and on partitions that are not active (yet marked in
use).
If you try to add a volume that would cause active partitions to over‐
lap, the volume is not added and a message similar to the following is
displayed: Error: /dev/rdisk/dsk1g or an overlapping partition is open.
addvol: Can't add volume '/dev/rdisk/dsk1g' to domain 'proj_x'
If you try to add a volume that would cause inactive partitions to
overlap, the volume is not added and a message similar to the following
is displayed. Subsequently, you can examine and change the disk label
and then run the addvol utility to add the volume. Error: Parti‐
tion(s) that overlap /dev/rdisk/dsk1g are marked in use. To edit an
incorrect disklabel, use the -e option with disklabel;
for more information see the disklabel(8) reference page. addvol:
Can't add volume '/dev/rdisk/dsk1g' to domain 'blegga'
Use the -F option to disable testing for overlap.
Caution
Disabling the overlap check can result in extensive data loss and
should be used with extreme caution.
Adding volumes to a domain does not affect the logical structure of the
filesets within the domain. You can add a volume to an active domain
while its filesets are mounted and in use.
Domains created prior to Version 5.0 or created with the -V3 option of
the mkfdmn command that contain a very large number of files may need
added BMT mcells (similar to inodes in UFS). By default, AdvFS
attempts to grow the BMT by 128 pages each time additional mcells are
needed. This may cause the metadata storage to become very fragmented,
resulting in a premature “out of disk space” error.
You can reduce the amount of BMT metadata fragmentation for domains
created prior to Version 5.0 or created with the -V3 option of the
mkfdmn command either by preallocating space for the BMT or by
increasing the number of pages that the system attempts to grow the BMT
each time space is needed. Use the -p option to preallocate all the BMT
space you expect the domain to need. Note that space that is preallo‐
cated cannot be deallocated. Use the -x option to specify how many
pages the BMT should be extended each time additional mcells are
needed.
The following table provides guidelines for BMT growth size in pages
(-x option) and BMT preallocation (-p option). If your estimated num‐
ber of files is greater than those listed in the table, keep doubling
the last table entry until you get a value that is close to your needs.
─────────────────────────────────────────────────────────────────────
Number of Files BMT Growth Size in pages BMT Preallocation
Size in pages
─────────────────────────────────────────────────────────────────────
Less than 50,000 default (128) 3,600
100,000 256 7,200
200,000 512 14,400
300,000 768 21,600
400,000 1024 28,800
800,000 2048 57,600
─────────────────────────────────────────────────────────────────────
To get the maximum benefit from increasing the number of metadata table
extent pages, use the same number of pages when adding a volume with
the addvol command as was assigned when the domain was created with the
mkfdmn command.
NOTES
This command supports shorthand names for LSM volume names. For exam‐
ple, if you enter the following: # addvol testdg.vol1 dom1
the volume name will be translated to: # addvol /dev/vol/testdg/vol1
dom1
RESTRICTIONS
You must be the root user to use this utility.
AdvFS does not support a multivolume root file system. You cannot use
the addvol utility to expand root_domain. This does not apply to clus‐
ter root domains.
ERRORS
Command execution continues after the following warnings are displayed:
addvol: Invalid value for -x addvol: Setting to minimum value of 128
Explanation:
You have entered an invalid value for the -x option. addvol:
Invalid value for -p addvol: Setting to minimum value of 0.
Explanation:
You have entered an invalid value for the -p option.
EXAMPLES
The following example adds a new volume to an active domain called
accounts_dmn. After the new volume is added, the balance command is run
to even the distribution of files over all of the volumes in the
domain. # addvol /dev/disk/dsk1c accounts_dmn # balance accounts_dmn
The /etc/fdmns/accounts_dmn subdirectory now includes new
entries for two volumes. The following example sets up a domain
for a news service that will handle as many as 400,000 files.
The news_dmn domain will contain two volumes that are configured
with preallocated BMT and increased extent sizes to accommodate
the large number of files. # mkfdmn -p 14400 -x 1024
/dev/disk/dsk1c news_dmn # addvol-p 14400 -x 1024
/dev/disk/dsk2c news_dmn
FILES
Specifies the command path. Contains domain names and devices.
SEE ALSO
Commands: advscan(8), disklabel(8), mkfdmn(8), rmvol(8)
Files: advfs(4), fdmns(4)addvol(8)
