The
restore command performs the inverse function of
dump(8). A full backup of a file system may be restored and subsequent incremental backups layered on top of it. Single files and directory subtrees may be restored from full or partial backups.
restore works across a network; to do this see the
-f flag described below. Other arguments to the command are file or directory names specifying the files that are to be restored. Unless the
-h flag is specified (see below), the appearance of a directory name refers to the files and (recursively) subdirectories of that directory.
If any file arguments are given with the
-x flag, or specified in the command shell with the
-i flag, the permissions of the root directory
will not be applied to the current directory, unless one of those file arguments explicitly represents the root inode (e.g.: a literal ‘.'). This is a change from the traditional behaviour, which used to be to always prompt the user.
Exactly one of the following flags is required:
-i
This mode allows interactive restoration of files from a dump. After reading in the directory information from the dump,
restore provides a shell like interface that allows the user to move around the directory tree selecting files to be extracted. The available commands are given below; for those commands that require an argument, the default is the current directory.
add [arg]
The current directory or specified argument is added to the list of files to be extracted. If a directory is specified, then it and all its descendants are added to the extraction list (unless the -h flag is specified on the command line). Files that are on the extraction list are prepended with a “*” when they are listed by ls.
cd arg
Change the current working directory to the specified argument.
delete [arg]
The current directory or specified argument is deleted from the list of files to be extracted. If a directory is specified, then it and all its descendants are deleted from the extraction list (unless the -h flag is specified on the command line). The most expedient way to extract most of the files from a directory is to add the directory to the extraction list and then delete those files that are not needed.
extract
All the files that are on the extraction list are extracted from the dump. restore will ask which volume the user wishes to mount. The fastest way to extract a few files is to start with the last volume, and work towards the first volume.
help, ?
List a summary of the available commands.
ls [arg]
List the current or specified directory. Entries that are directories are appended with a “/”. Entries that have been marked for extraction are prepended with a “*”. If the verbose flag is set the inode number of each entry is also listed.
pwd
Print the full pathname of the current working directory.
quit, xit
Restore immediately exits, even if the extraction list is not empty.
setmodes
All the directories that have been added to the extraction list have their owner, modes, and times set; nothing is extracted from the dump. This is useful for cleaning up after a restore has been prematurely aborted.
verbose
The sense of the -v flag is toggled. When set, the verbose flag causes the ls command to list the inode numbers of all entries. It also causes restore to print out information about each file as it is extracted.
what
List dump header information.
-R
restore requests a particular tape of a multi volume set on which to restart a full restore (see the -r flag below). This is useful if the restore has been interrupted.
-r
Restore (rebuild a file system). The target file system should be made pristine with
newfs(8), mounted and the user
cd(1)'d into the pristine file system before starting the restoration of the initial level 0 backup. If the level 0 restores successfully, the
-r flag may be used to restore any necessary incremental backups on top of the level 0. The
-r flag precludes an interactive file extraction and can be detrimental to one's health if not used carefully (not to mention the disk). An example:
newfs /dev/rsd0g
mount /dev/sd0g /mnt
cd /mnt
restore rf /dev/rst0
Note that
restore leaves a file
restoresymtable in the root directory to pass information between incremental restore passes. This file should be removed when the last incremental has been restored.
restore, in conjunction with
newfs(8) and
dump(8), may be used to modify file system parameters such as size or block size.
-t
The names of the specified files are listed if they occur on the backup. If no file argument is given, then the root directory is listed, which results in the entire content of the backup being listed, unless the -h flag has been specified. Note that the -t flag replaces the function of the old dumpdir program.
-x
The named files are read from the given media. If a named file matches a directory whose contents are on the backup and the -h flag is not specified, the directory is recursively extracted. The owner, modification time, and mode are restored (if possible). If no file argument is given, then the root directory is extracted, which results in the entire content of the backup being extracted, unless the -h flag has been specified.
The following additional options may be specified:
-b bsize
The number of kilobytes per dump record. If the -b option is not specified, restore tries to determine the block size dynamically.
-c
Normally, restore will try to determine dynamically whether the dump was made from an old (pre-4.4) or new format file system. The -c flag disables this check, and only allows reading a dump in the old format.
-D algorithm
Computes the digest of each regular files using the algorithm and output to standard output. The algorithm is one of md5, rmd160, or sha1. This option doesn't imply -N.
-f file
Read the backup from
file;
file may be a special device file like
/dev/rst0 (a tape drive),
/dev/rsd1c (a disk drive), an ordinary file, or ‘
-' (the standard input). If the name of the file is of the form “host:file”, or “user@host:file”,
restore reads from the named file on the remote host using
rmt(8). If the name of the file is ‘
-',
restore reads from standard input. Thus,
dump(8) and
restore can be used in a pipeline to dump and restore a file system with the command
dump 0f - /usr | (cd /mnt; restore xf -)
-h
Extract the actual directory, rather than the files that it references. This prevents hierarchical restoration of complete subtrees from the dump.
-M mfile
Do not set the file flags on restore. Instead, append an
mtree(8) specification to
mfile, which can be used to restore file flags with a command such as
sort mfile | mtree -e -i -u
-m
Extract by inode numbers rather than by file name. This is useful if only a few files are being extracted, and one wants to avoid regenerating the complete pathname to the file.
-N
Do not perform actual writing to disk.
-s fileno
Read from the specified fileno on a multi-file tape. File numbering starts at 1.
-u
The -u (unlink) flag removes files before extracting them. This is useful when an executable file is in use. Ignored if -t or -N flag is given.
-v
Normally restore does its work silently. The -v (verbose) flag causes it to type the name of each file it treats preceded by its file type.
-y
Do not ask the user whether to abort the restore in the event of an error. Always try to skip over the bad block(s) and continue.