Content-type: text/html Man page of volrestore

volrestore

Section: Maintenance Commands (8)
Index Return to Main Contents
 

NAME

volrestore - Restore complete or partial Logical Storage Manager (LSM) configuration  

SYNOPSIS

/usr/sbin/volrestore [-b] [-f] [-d dir] [-i] [-g diskgroup] [-v volume...]

/usr/sbin/volrestore [-l] [-d dir] [-g diskgroup] [-v volume...]


 

OPTIONS

Requests the "best possible" restoration after certain types of volrestore failures. This option is useful when the failure was caused by a missing disk or by a conflict between the current LSM configuration and the saved LSM configuration. Specifies the directory where the description files you want to use are located. The default directory is the directory under /usr/var/lsm/db with the latest timestamp. Forces the volrestore command to execute, after the checksum validation has failed. This option is used when the saved LSM configuration has been manually edited (for example, to remove configuration information for plexes on failed disks). Specifies the disk group whose configuration you want to restore or display. Specifies an interactive restore session, in which volrestore prompts before restoring each disk group. Lists the configuration information that was backed up using volsave. Specifies one or more volumes whose configuration you want to restore or display.
 

DESCRIPTION

The volrestore command restores an LSM configuration database that was backed up using the volsave command.

The volsave command saves configuration information in a set of files, called a description set. Included in the description set is a file containing a checksum, a magic number, the date of the file's creation, and the version number of the volsave command. Before the volrestore command restores the LSM configuration from the description set, it validates the checksum and the magic number.

By default, the volrestore command uses the description files in the directory under /usr/var/lsm/db that has the latest timestamp. If you used the -d option with volsave to save the LSM configuration in a directory other than the default, use the -d option to specify that directory to volrestore.

To display the latest LSM configuration saved in a description set, use the -l option. You can use the -l and -d options together to display any description set saved in any directory.

You can use volrestore to restore specific volumes in a disk group and specific disk groups. The volrestore command attempts to reimport the disk group based on configuration information on disks which belong to the disk group. If the import fails, the disk group is re-created by reinitializing all disks within that disk group and re-creating all volumes, unassociated plexes, and unassociated subdisks, based on information in the volmake description file.

If you specify the -i option, volrestore runs in interactive mode and prompts you before restoring a disk group. In ASE or clusters configurations, this mode is the default.

You can also restore a complete LSM configuration. In this case, volrestore attempts to reenable the vold daemon based on all rootdg disks in the saved copy of the /etc/vol/volboot file (volboot).

If vold cannot be enabled, you are given the option of re-creating the rootdg disk group and any other disk groups using the saved LSM description set. The rootdg disk group is re-created first, and vold is put in the enabled mode. Then, the other disk groups are re-created. The disk groups are re-created by first attempting to import them based on available disks in that disk group. If the import fails, the disk group is reinitialized and all volumes in that disk group are also re-created based on the volmake description files.
 

Conflicts while Restoring the Configuration

When volrestore executes, it can encounter conflicts in the LSM configuration. For example, a disk may be missing, or another volume may be using the same plex name, subdisk name, or location on a disk. Configuration conflicts usually arise because the LSM configuration was changed after it was saved using volsave(8).

When volrestore finds a conflict, it displays error messages and the configuration of the volume, as found in the saved LSM description set. In addition, it removes all volumes created in that disk group during the restoration. The disk group that had the conflict remains imported, and volrestore continues to restore other disk groups.

If volrestore fails because of a conflict, you can use the -b option to do the "best possible" restoration in a disk group. You will then have to resolve the conflicts and restore the volumes in the affected disk group. You can resolve the conflicts in two ways: Check the current configuration of the diskgroup and make any changes to remove the conflict. For example, rename any plexes or subdisks that have duplicate names. The error messages from volrestore provide information on what the conflict is. Manually edit the volmake description file for that disk group in the directory that is being used by the volrestore command.
 

Failures in Restoring the Configuration

Restoration of volumes fails if one or more disks associated with the volumes are unavailable, for example due to disk failure. This can, in turn, cause failure in restoring a disk group. You can use a command like the following to restore the LSM configuration of a disk group: # volrestore -b -g diskgroup

The volumes associated with the failed disks can then be restored by editing the volmake description file to remove the plexes that use the failed disks. Note that editing the description file will affect the checksum of the files in the backup directory, so you will have to override the checksum validation by using the -f option. You can use the -v option to restore the specific volumes that had not been restored.

When volumes are restored using the volmake description file, the plexes are created in the DISABLED EMPTY state. The volrestore command does not attempt to start or enable such volumes. You must use volmend or volume to set the plex states appropriately before starting the volume. The volrestore command warns you to check the state of each disk associated with a volume before using volmend or volume to set plex states; to carefully find out which disks in the LSM configuration could have had failures since saving the LSM configuration; and to use volmend or volume to mark plexes on those disks to be STALE. In addition, any plex that was detached or disabled at any point during or after the LSM configuration was saved should be marked STALE.
 

RESTRICTIONS

The volrestore command does not restore volumes associated with the root, swap, /usr and /var filesystems. See the manual Logical Storage Manager for information on reencapsulating the disk partitions associated with root, swap, /usr and /var.

The following restrictions apply to ASE or clusters configurations: The -i and -g options are required with volrestore. LSM disk groups can only be restored one at a time. Before using volrestore, the directory with the latest LSM configuration for a disk group across all ASE or cluster nodes should be determined.
 

FILES

Default directory in which volsave creates the timestamped subdirectories with LSM description sets. File containing the checksum that volrestore validates before executing. Saved copy of the /etc/vol/volboot file. Description file that can be used by the volmake command. There is one file for each disk group.
 

SEE ALSO

Commands: volmake(4), volsave(8), volmend(8), volmake(8), volume(8)

Guides: Logical Storage Manager


 

Index

NAME
SYNOPSIS
OPTIONS
DESCRIPTION
Conflicts while Restoring the Configuration
Failures in Restoring the Configuration
RESTRICTIONS
FILES
SEE ALSO

This document was created by man2html, using the manual pages.
Time: 02:40:31 GMT, October 02, 2010