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RESTORE(8) BSD System Manager’s Manual RESTORE(8)
NAME
restore ? restore files or file systems from backups made with dump |
SYNOPSIS
restore ?C [?ckMvy] [?b blocksize] [?D filesystem] [?f file] [?s fileno] [?T directory] |
restore ?i [?chkmMNuvy] [?b blocksize] [?f file] [?s fileno] [?T directory] |
restore ?R [?ckMNuvy] [?b blocksize] [?f file] [?s fileno] [?T directory] |
restore ?r [?ckMNuvy] [?b blocksize] [?f file] [?s fileno] [?T directory] |
restore ?t [?chkMNuvy] [?b blocksize] [?f file] [?s fileno] [?T directory] [?X filelist] [file ...] |
restore ?x [?chkmMNuvy] [?b blocksize] [?f file] [?s fileno] [?T directory] [?X filelist] [file ...] (The 4.3BSD option syntax is implemented for backward compatibility but is not documented here.) |
DESCRIPTION |
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. Exactly one of the following flags is required: |
?C’ This mode allows comparison of files from a dump. Restorereads the backup and compares its contents with files present onthe disk. It first changes its working directory to the root ofthe filesystem that was dumped and compares the tape with thefiles in its new current directory.
?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] cd arg’ Change the current working directory to the specified argument. delete [arg] extract’ All files 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’ Restore immediately exits, even if the extraction list is not empty. setmodes’ All 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. ?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 mke2fs(8), mounted, and the user cd’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 (not to mention the disk) if not used carefully. An example: mke2fs /dev/sda1 restore rf /dev/st0 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 mke2fs(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 onthe backup. If no file argument is given, the root directory islisted, which results in the entire content of the backup beinglisted, unless the ?h flag has been specified. Note that the ?tflag replaces the function of the old dumpdir(8) program. Seealso the ?X option below.
?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, the root directory is extracted, which results in the entire content of the backup being extracted, unless the ?h flag has been specified. See also the ?X option below. The following additional options may be specified: ?b blocksize ?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 filesystem ?f file ?k’ Use Kerberos authentication when contacting the remote tape server. (Only available if this options was enabled when restore was compiled.) ?h’ Extract the actual directory, rather than the files that it references. This prevents hierarchical restoration of complete subtrees from the dump. ?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. ?M’ Enables the multi-volume feature (for reading dumps made using the ?M option of dump). The name specified with ?f is treated as a prefix and restore tries to read in sequence from <prefix>001, <prefix>002 etc. ?N’ The ?N flag causes restore to only print file names. Files are not extracted. ?s fileno ?T directory ?u’ When creating certain types of files, restore may generate a warning diagnostic if they already exist in the target directory. To prevent this, the ?u (unlink) flag causes restore to remove old entries before attempting to create new ones. ?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. ?X filelist ?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. DIAGNOSTICS |
Complains if it gets a read error. If ?y has been specified, or the user responds ’y’, restore will attempt to continue the restore. If a backup was made using more than one tape volume, restore will notify the user when it is time to mount the next volume. If the ?x or ?i flag has been specified, restore will also 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. There are numerous consistency checks that can be listed by restore. Most checks are self-explanatory or can ‘‘never happen’’. Common errors are given below. |
Converting to new file system format
A dump tape created from the old file system has been loaded. It is automatically converted to the new file system format. <filename>: not found on tape expected next file <inumber>, got
<inumber> Incremental dump too low Incremental dump too high Tape read error while restoring <filename> resync restore, skipped <num> blocks Restore exits with zero status on success. Tape errors are indicated with an exit code of 1. When doing a comparison of files from a dump, an exit code of 2 indicates that some files were modified or deleted since the dump was made. ENVIRONMENT |
If the following environment variable exists it will be utilized by restore: |
TAPE’ If no -f option was specified, restore will use the devicespecified via TAPE as the dump device. TAPE may be of the form"tapename", "host:tapename" or "user@host:tapename".
TMPDIR FILES |
/dev/st0’ the default tape drive
/tmp/rstdir*’ file containing directories on the
tape SEE ALSO |
dump(8), mount(8), mke2fs(8), rmt(8) |
BUGS
Restore can get confused when doing incremental restores from dumps that were made on active file systems. A level 0 dump must be done after a full restore. Because restore runs in user code, it has no control over inode allocation; thus a full dump must be done to get a new set of directories reflecting the new inode numbering, even though the content of the files is unchanged. The temporary files /tmp/rstdir* and /tmp/rstmode* are generated with a unique name based on the date of the dump and the process ID (see mktemp(3) ), except when ?r or ?R is used. Because ?R allows you to restart a ?r operation that may have been interrupted, the temporary files should be the same across different processes. In all other cases, the files are unique because it is possible to have two different dumps started at the same time, and separate operations shouldn’t conflict with each other. To do a network restore, you have to run restore as root or use a remote shell replacement (see RSH variable). This is due to the previous security history of dump and restore. (restore is written to be setuid root, but we are not certain all bugs are gone from the restore code - run setuid at your own risk.) |
AUTHOR
The dump/restore backup suit was ported to Linux’s Second Extended File System by Remy Card <card@Linux.EU.Org>. He maintained the initial versions of dump (up and including 0.4b4, released in january 1997). Starting with 0.4b5, the new maintainer is Stelian
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AVAILABILITY
The dump/restore backup suit is available from |
HISTORY
The restore command appeared in 4.2BSD. restore 0.4b19 August 20, 2000 restore 0.4b19 |