# Administration Reference

## backup volrestore

Purpose

Restores one or more volumes

Synopsis

    backup volrestore -server <destination machine>
                      -partition <destination partition>
                      -volume <volume(s) to restore>+
                      [-extension <new volume name extension>]
                      [-date <date from which to restore>+]
                      [-portoffset <TC port offsets>+]  [-n]
                      [-localauth]  [-cell <cell name>]  [-help]

    backup volr -s <destination machine>  -pa <destination partition>
                -v <volume(s) to restore>+  [-e <new volume name extension>]
                [-d <date from which to restore>+]  [-po <TC port offsets>+]
                [-n]  [-l]  [-c <cell name>]  [-h]

Description

The backup volrestore command restores the contents of one or more volumes to the site indicated by the -server and -partition arguments. Use the command either to overwrite the contents of existing volumes with the restored data or to create new volumes while retaining the existing ones. The specified site does not have to be the current site for the volumes.

(If the FILE YES instruction appears in the /usr/afs/backup/CFG_device_name file associated with the specified port offset, then the backup volrestore command restores data from the backup data file listed for that port offset in the Tape Coordinator's /usr/afs/backup/tapeconfig file, rather than from tape. For the sake of clarity, the following text refers to tapes only, but the Backup System handles backup data files in much the same way.)

The command's arguments can be combined as indicated:

- To preserve a volume's current contents and also create a new volume to house the restored version, use the -extension argument. The Backup System creates the new volume on the server and partition named by the -server and -partition arguments, assigns it the same name as the current volume with the addition of the specified extension, and creates a new Volume Location Database (VLDB) entry for it. Creating a new volume enables the administrator to compare the two versions.

- To overwrite a volume's existing contents with the restored version, omit the -extension argument, and specify the site as indicated:

  - To retain the current site, specify it with the -server and -partition arguments.

  - To move the volume to a different site while overwriting it, specify the new site with the -server argument, -partition argument, or both. The Backup System creates a new volume at that site, removes the existing volume, and updates the site information in the volume's VLDB entry. The backup version of the volume is not removed automatically from the original site, if it exists. Use the vos remove command to remove it and the vos backup command to create a backup version at the new site.

- To restore a volume that no longer exists in the file system, specify its name with the -volume argument and use the -server and -partition arguments to place it at the desired site. The Backup System creates a new volume and new VLDB entry.

In each case, the command sets each volume's creation date to the date and time at which it restores it. The creation date appears in the `Creation` field in the output from the vos examine and vos listvol commands.

If restoring all of the volumes that resided on a single partition, it is usually more efficient to use the backup diskrestore command. If restoring multiple volumes to many different sites, it can be more efficient to use the backup volsetrestore command.

By default, the backup volrestore command restores the most recent full dump and all subsequent incremental dumps for each volume, bringing the restored volumes to the most current possible state. To restore the volumes to their state at some time in the past, use the -date argument. The Backup System restores the most recent full dump and each subsequent incremental dump for which the clone date of the volume included in the dump is before the indicated date and time (the clone date timestamp appears in the `clone date` field of the output from the backup volinfo command). For backup and read-only volumes, the clone date represents the time at which the volume was copied from its read/write source; for read/write volumes, it represents the time at which the volume was locked for inclusion in the dump. The resemblance of a restored volume to its actual state at the indicated time depends on the amount of time that elapsed between the volume's clone date in the last eligible dump and the specified time.

If the -volume argument specifies the base (read/write) form of the volume name, the Backup System searches the Backup Database for the newest dump set that includes a dump of either the read/write or the backup version of the volume. It restores the dumps of that version of the volume, starting with the most recent full dump. If, in contrast, the volume name explicitly includes the .backup or .readonly extension, the Backup System restores dumps of the corresponding volume version only.

To generate a list of the tapes the Backup System needs to perform the restore operation, without actually performing it, combine the -n flag with the options to be used on the actual command.

If all of the full and incremental dumps of all relevant volumes were not written to a type of tape that a single Tape Coordinator can read, use the -portoffset argument to list multiple port offset numbers in the order in which the tapes are needed (first list the port offset for the full dump, second the port offset for the level 1 incremental dump, and so on). If restoring multiple volumes, the same ordered list of port offsets must apply to all of them. If not, either issue this command separately for each volume, or use the vos volsetrestore command after defining groups of volumes that were dumped to compatible tape types. For further discussion, see the AFS Administration Guide.

The Tape Coordinator's default response to this command is to access the first tape it needs by invoking the MOUNT instruction in the local /usr/afs/backup/CFG_device_name file, or by prompting the backup operator to insert the tape if there is no MOUNT instruction. However, if the AUTOQUERY NO instruction appears in the CFG_device_name file, or if the issuer of the butc command included the -noautoquery flag, the Tape Coordinator instead expects the tape to be in the device already. If it is not, or is the wrong tape, the Tape Coordinator invokes the MOUNT instruction or prompts the operator. It also invokes the MOUNT instruction or prompts for any additional tapes needed to complete the restore operation; the backup operator must arrange to provide them.

Options

-server
  Names the file server machine on which to restore each volume. If this argument and the -partition argument indicate a site other than the current site for each volume, and the -extension argument is not also provided, the Backup System removes the existing volumes from their current sites, places the restored contents at the specified site, and changes the site information in the volume's VLDB entry.

-partition
  Names the partition to which to restore each volume. If this argument and the -server argument indicate a site other than the current site for each volume, and the -extension argument is not also provided, the Backup System removes the existing volumes from their current sites, places the restored contents at the specified site, and changes the site information in the volume's VLDB entry.

-volume
  Names one or more volumes to restore, using the volume name as listed in the Backup Database. Provide the base (read/write) name of each volume to have the Backup System search the Backup Database for the newest dump set that includes a dump of either the read/write or the backup version of the volume; it restores the dumps of that version of the volume, starting with the most recent full dump. If, in contrast, a volume name explicitly includes the .backup or .readonly extension, the Backup System restores dumps of the corresponding volume version only.

-extension
  Creates a new volume to house the restored data, with a name derived by appending the specified string to each volume named by the -volume argument. The Backup System creates a new VLDB entry for the volume. Any string other than .readonly or .backup is acceptable, but the combination of the existing volume name and extension cannot exceed 22 characters in length. To use a period to separate the extension from the name, specify it as the first character of the string (as in .rst, for example).

-date
  Specifies a date and optionally time; the restored volume includes data from dumps performed before the date only. Provide a value in the format mm/dd/yyyy [hh:MM], where the required mm/dd/yyyy portion indicates the month (mm), day (dd), and year (yyyy), and the optional hh:MM portion indicates the hour and minutes in 24-hour format (for example, the value 14:36 represents 2:36 p.m.). If omitted, the time defaults to 59 seconds after midnight (00:00:59 hours).

  Valid values for the year range from 1970 to 2037; higher values are not valid because the latest possible date in the standard UNIX representation is in February 2038. The command interpreter automatically reduces any later date to the maximum value.

  If this argument is omitted, the Backup System restores all possible dumps including the most recently created.

  Note: | A plus sign follows this argument in the command's syntax statement because it accepts a multiword value which does not need to be enclosed in double quotes or other delimiters, not because it accepts multiple dates. Provide only one date (and optionally, time) definition.

-portoffset
  Specifies one or more port offset numbers (up to a maximum of 128), each corresponding to a Tape Coordinator to use in the operation. If there is more than one value, the Backup System uses the first one when restoring the full dump of each volume, the second one when restoring the level 1 incremental dump of each volume, and so on. It uses the final value in the list when restoring dumps at the corresponding depth in the dump hierarchy and all dumps at lower levels.

  Provide this argument unless the default value of 0 (zero) is appropriate for all dumps. If 0 is just one of the values in the list, provide it explicitly in the appropriate order.

-n
  Displays the list of tapes that contain the dumps required by the restore operation, without actually performing the operation.

-localauth
  Constructs a server ticket using a key from the local /usr/afs/etc/KeyFile file. The backup command interpreter presents it to the Backup Server, Volume Server and VL Server during mutual authentication. Do not combine this flag with the -cell argument. For more details, see the introductory backup reference page.

-cell
  Names the cell in which to run the command. Do not combine this argument with the -localauth flag. For more details, see the introductory backup reference page.

-help
  Prints the online help for this command. All other valid options are ignored.

Output

If the issuer includes the -n flag with the command, the following string appears at the head of the list of the tapes necessary to complete the restore operation.

       Tapes needed:

Examples

The following command restores the volume user.pat to partition /vicepa on machine fs5.abc.com:

       % backup volrestore -server fs5.abc.com -partition a -volume user.pat

The following command restores the volumes user.smith and user.terry to partition /vicepb on machine fs4.abc.com, adding a .rst extension to each volume name and preserving the existing user.smith and user.terry volumes. Only dumps created before 5:00 p.m. on 31 January 1998 are restored. (The command is shown here on multiple lines only for legibility reasons.)

       % backup volrestore -server fs4.abc.com -partition b  \
                           -volume user.smith user.terry  \
                           -extension .rst -date 1/31/1998 17:00

The following command restores the volume user.pat to partition /vicepb on machine fs4.abc.com. The Tape Coordinator with port offset 1 handles the tape containing the full dump; the Tape Coordinator with port offset 0 handles all tapes containing incremental dumps. (The command is shown here on two lines only for legibility reasons.)

       % backup volrestore -server fs5.abc.com -partition a  \
                           -volume user.pat -portoffset 1 0

Privilege Required

The issuer must be listed in the /usr/afs/etc/UserList file on every machine where the Backup Server or Volume Location (VL) Server is running, and on every file server machine that houses an affected volume. If the -localauth flag is included, the issuer must instead be logged on to a server machine as the local superuser root.

Related Information

backup

backup dump

backup diskrestore

backup volsetrestore

butc

vos backup

vos remove

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