vgscan(1M)vgscan(1M)NAMEvgscan - scan physical volumes for LVM volume groups
SYNOPSIS
| | | vg_names...]
Remarks
If the volume group input arguments belong to a combination of volume
groups version 1.0 and 2.0 or higher, the arguments may not be pro‐
cessed in the order they are listed on the command line.
DESCRIPTION
The command is used as follows:
1. Recovering and recreating the or file when the file has been deleted
or does not match the current physical volumes.
2. Reporting device special file lists for unconfigured volume groups.
For recovery, will add entries for volume groups that are missing from
or The command recovers volume group information by using LVM data
structures in kernel memory, and by probing all devices, searching for
LVM disks. If one or more physical volumes in the volume group has
more than 8 paths, the command will only include 8 paths per physical
volume. Additional path(s) will not be added in the or file. The vol‐
ume group device special file must be present for recovery to succeed.
In addition, will recover a missing volume group only if it has been
activated at least once since the last boot or the last import, and the
Volume Group ID is unique (see the section).
Unconfigured volume groups are volume groups residing on attached stor‐
age that are missing from or and have not been activated since the last
boot. The command cannot recover the or entries for these volume
groups. Instead, it will print out the physical volume device special
files for these volume groups. Configure these volume groups using the
command. See vgimport(1M).
The command will not update existing volume group entries in or unless
the option is used. The option can be used to overwrite existing vol‐
ume group entries in or Otherwise, or should be moved before running in
order for the options to take full effect.
In HP-UX 11i Version 3, the Mass Storage Stack supports two naming con‐
ventions for the device special files used to identify devices (see
intro(7) and lvm(7)). Devices are represented as follows:
· Persistent device special files,
· Legacy device special files,
LVM supports the use of both conventions within the same volume group.
The command provides several options for controlling the use of legacy
and persistent DSFs (device special files) during the or recovery. By
default, will populate or with legacy DSFs, including alternate paths.
There is one exception:
For activated volume groups that are using persistent DSFs, will
populate or using persistent DSFs for those physical volumes.
The and options allow the user to override this default behav‐
ior.
Options and Arguments
recognizes the following options and arguments:
Scan all paths of multipathed physical volumes. The
option cannot be used in conjunction with the and
options and when the legacy naming model is dis‐
abled with the command (see rmsf(1M)).
Populate or using both persistent and legacy DSFs. Per‐
sistent DSFs will be added before legacy DSFs, so
they will be used as the primary path. This
option can be used to migrate a deactivated vol‐
ume group using legacy DSFs to use both persis‐
tent and legacy DSFs. The option cannot be used
in conjunction with the and options and when the
legacy naming model is disabled with the command
(see rmsf(1M)).
For the specified volume groups, force
to replace any existing entries in or with
updated entries. If the volume groups are miss‐
ing from or they are added. The option provides
the following functions:
(1) Update incorrect, existing entries for
activated volume groups. For example, a
volume group may have been imported with
only a partial set of devices. Or, a boot
volume group may have been activated with
persistent DSFs, while the existing entry
in or has legacy DSFs.
(2) Migrate a deactivated volume group using
legacy DSFs to use persistent DSFs, or
vice-versa.
(3) Add volume group entries to the or file in
the order specified on the command line.
For example, this option can be used to
put the boot volume group first in the or
file.
With the option, will not search for additional
volume groups and will not report unconfigured
volume groups.
Skip the disk probe portion of
and retrieve volume group information only from
LVM data structures in kernel memory. The disk
probe portion can be a time consuming operation,
so this option can be used for faster recovery of
or However, with this option, only volume groups
currently activated are added to or For deacti‐
vated volume groups, no information is added to
or The option cannot be used in conjunction with
the and options.
Populate or using persistent DSFs, with the following
exception:
If there are volume groups activated that are
using legacy DSFs, then will populate or using
legacy DSFs for those physical volumes.
The option cannot be used in conjunction with the
and options.
Preview the actions that would be taken but do not update
or This option is best used in conjunction with
the option. As with other options, if the legacy
naming model has been disabled with the command
(see rmsf(1M)), the option should also be used
with the option.
Print verbose messages.
EXTERNAL INFLUENCES
Environment Variables
determines the language in which messages are displayed.
If is not specified or is null, it defaults to "C" (see lang(5)).
If any internationalization variable contains an invalid setting, all
internationalization variables default to "C" (see environ(5)).
EXAMPLES
1. Append entries for volume groups missing from the or file. For
deactivated volume groups, use legacy DSFs, and for activated volume
groups, use the DSFs that were used to activate them. Report all
physical volume legacy DSFs belonging to unconfigured volume groups.
Do not modify existing volume group entries in or Run without any
options:
2. Recreate the or file for volume groups activated since the last
boot. For deactivated volume groups, use legacy DSFs, and for acti‐
vated volume groups, use the DSFs that were used to activate them.
Report all physical volume legacy DSFs belonging to unconfigured
volume groups.
or
3. Recreate the or file for volume groups activated since the last
boot. For deactivated volume groups, use persistent DSFs, and for
activated volume groups, use the DSFs that were used to activate
them. Report all physical volume persistent DSFs belonging to
unconfigured volume groups.
or
4. Recreate the or file for volume groups activated since the last
boot. For activated and deactivated volume groups, use both persis‐
tent and legacy DSFs. Report all physical volume persistent and
legacy DSFs belonging to unconfigured volume groups.
or
5. Recreate the or file for activated volume groups, using the DSFs
that were used to activate them. For deactivated volume groups, no
entries are added to or and no physical volume DSFs are reported.
or
6. For the volume group overwrite the existing physical volume DSFs in
or with the physical volume persistent DSFs found belonging to dur‐
ing a hardware probing of all devices.
7. For the volume group overwrite the existing physical volume DSFs in
or with the physical volume DSFs used in kernel memory. The volume
group must be activated, or this command will fail.
8. Recreate the or file with the volume groups and The volume group
entries will be added to or in that order. For deactivated volume
groups, use legacy DSFs, and for activated volume groups, use the
DSFs that were used to activate them. Do not add any other volume
groups.
or
To preview the output for any of the above examples, include the and
options in the command lines.
WARNINGS
The option may become obsolete in future releases.
The option may become obsolete in future releases.
For deactivated volume groups, cannot recover volume groups that do not
have a unique Volume Group ID, that is, when two or more volume groups
share the same ID. If this scenario occurs, the command must be used
to assign a unique Volume Group ID for each volume group. See
vgchgid(1M).
After running the number and order of physical volumes in the recon‐
structed or file could be different than what was configured previously
(even if the option is used). The results could be as follows:
The designated primary and alternate paths may not be the same
as was configured before.
Alternate paths will be added to the or file even though they
weren't initially configured in the volume group.
The boot information may be incorrect, due to changed order of
device special files in the new or file.
Rectify the above problems as follows:
Run to activate all deactivated volume groups. For shared vol‐
ume groups, invoke to activate the shared volume group in exclu‐
sive mode.
Invoke to remove any unwanted alternate paths which were added
to the or file as a result of the invocation.
For boot volume groups only, invoke to correct the boot informa‐
tion on the physical volumes.
If the original primary path of a physical volume is now config‐
ured as an alternate, the order can be reversed by using to
remove the primary path and then invoking to add it back.
The command will also print the following warning messages to notify
the user of the above problems:
No more than 8 paths to any Physical Volume will be added to the or
file. All other paths will be omitted.
SEE ALSOlvlnboot(1M), vgchange(1M), vgcreate(1M), vgextend(1M), vgexport(1M),
vgimport(1M), vgreduce(1M), intro(7), lvm(7).
vgscan(1M)