Content-type: text/html Man page of voldg

voldg

Section: Maintenance Commands (8)
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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: 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)). 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. 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. 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. 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. 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. 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. 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)


 

Index

NAME
SYNOPSIS
DESCRIPTION
SEE ALSO

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Time: 02:40:39 GMT, October 02, 2010