# xfsrestore - XFS filesystem incremental restore utility - man(8) - [phpMan] [_xfsrestore_(8)](https://www.chedong.com/phpMan.php/man/xfsrestore/8/markdown) System Manager's Manual [_xfsrestore_(8)](https://www.chedong.com/phpMan.php/man/xfsrestore/8/markdown) ## NAME xfsrestore - XFS filesystem incremental restore utility ## SYNOPSIS **xfsrestore **-h **xfsrestore **[ options ] -f _source_ [ -f _source_ ... ] _dest_ **xfsrestore **[ options ] - _dest_ **xfsrestore **-I [ subopt=value ... ] ## DESCRIPTION _xfsrestore_ restores filesystems from dumps produced by [_xfsdump_(8)](https://www.chedong.com/phpMan.php/man/xfsdump/8/markdown). Two modes of operation are available: simple and cumulative. The default is simple mode. _xfsrestore_ populates the specified destination directory, _dest_, with the files contained in the dump media. The **-r **option specifies the cumulative mode. Successive invocations of _xfsrestore_ are used to apply a chronologically ordered sequence of delta dumps to a base (level 0) dump. The contents of the filesystem at the time each dump was produced is reproduced. This can in‐ volve adding, deleting, renaming, linking, and unlinking files and directories. A delta dump is defined as either an incremental dump (_xfsdump_ **-l **option with level > 0) or a resumed dump (_xfsdump_ **-R **option). The deltas must be applied in the order they were pro‐ duced. Each delta applied must have been produced with the previously applied delta as its base. _xfsrestore_ keeps state information in the _xfsrestorehousekeepingdir_, to inform subsequent in‐ vocations when used in cumulative mode, or in the event a restore is interrupted. To ensure that the state information can be processed, a compatible version of _xfsrestore_ must be used for each subsequent invocation. Additionally, each invocation must run on a system of the same endianness and page size. The options to _xfsrestore_ are: ### -a _ Each invocation of _xfsrestore_ creates a directory called _xfsrestorehousekeepingdir_. This directory is normally created directly under the _dest_ directory. The **-a **option al‐ lows the operator to specify an alternate directory, _housekeeping_, in which _xfsrestore_ creates the _xfsrestorehousekeepingdir_ directory. When performing a cumulative (**-r **op‐ tion) restore or resuming (**-R **option) a restore, each successive invocation must specify the same alternate directory. ### -b _ Specifies the blocksize, in bytes, to be used for the restore. For other drives such as DAT or 8 mm , the same blocksize used for the xfsdump operation must be specified to re‐ store the tape. The default block size is 1Mb. ### -c _ Use the specified program to alert the operator when a media change is required. The alert program is typically a script to send a mail or flash a window to draw the opera‐ tor's attention. ### -e ### -f _ -f _ Specifies a source of the dump to be restored. This can be the pathname of a device (such as a tape drive), a regular file or a remote tape drive (see [_rmt_(8)](https://www.chedong.com/phpMan.php/man/rmt/8/markdown)). This option must be omitted if the standard input option (a lone **- **preceding the _dest_ specification) is specified. ### -i interactive dialogue is begun. The operator uses a small set of commands to peruse the directory hierarchy, selecting files and subtrees for extraction. The available com‐ mands are given below. Initially nothing is selected, except for those subtrees speci‐ fied with **-s **command line options. **ls **[_arg_] List the entries in the current directory or the specified directory, or the specified non-directory file entry. Both the entry's original inode number and name are displayed. Entries that are directories are appended with a `/'. Entries that have been selected for extraction are prepended with a `*'. **cd **[_arg_] Change the current working directory to the specified argument, or to the filesystem root directory if no argument is specified. **pwd **Print the pathname of the current directory, relative to the filesystem root. **add **[_arg_] The current directory or specified file or directory within the current directory is selected for extraction. If a directory is specified, then it and all its descendents are selected. Entries that are selected for extraction are prepended with a `*' when they are listed by **ls**. **delete **[_arg_] The current directory or specified file or directory within the current directory is deselected for extraction. If a directory is specified, then it and all its descendents are deselected. The most expedient way to extract most of the files from a directory is to select the directory and then deselect those files that are not needed. **extract **Ends the interactive dialogue, and causes all selected subtrees to be re‐ stored. **quit _**xfsrestore_ ends the interactive dialogue and immediately exits, even if there are files or subtrees selected for extraction. **help **List a summary of the available commands. ### -m size to be used (see **-b **option above). ### -n _ Allows _xfsrestore_ to restore only files newer than _file_. The modification time of _file_ (i.e., as displayed with the **ls -l **command) is compared to the inode modification time of each file on the source media (i.e., as displayed with the **ls -lc **command). A file is restored from media only if its inode modification time is greater than or equal to the modification time of _file_. ### -o user id of root, _xfsrestore_ restores owner and group of each file and directory. When run with any other effective user id it does not, unless this option is specified. ### -p _ Causes progress reports to be printed at intervals of _interval_ seconds. The interval value is approximate, _xfsrestore_ will delay progress reports to avoid undue processing overhead. ### -q _srestore_ must make special allowances. ### -r -a same for each invocation. ### -s _ Specifies a subtree to restore. Any number of **-s **options are allowed. The restore is constrained to the union of all subtrees specified. Each subtree is specified as a pathname relative to the restore _dest_. If a directory is specified, the directory and all files beneath that directory are restored. ### -t ries. It may be desirable to set the verbosity level to **silent **when using this option. ### -v _ ### -v _ Specifies the level of detail used for messages displayed during the course of the re‐ store. The _verbosity_ argument can be passed as either a string or an integer. If passed as a string the following values may be used: **silent**, **verbose**, **trace**, **debug**, or **nitty**. If passed as an integer, values from 0-5 may be used. The values 0-4 correspond to the strings already listed. The value 5 can be used to produce even more verbose debug out‐ put. The first form of this option activates message logging across all restore subsystems. The second form allows the message logging level to be controlled on a per-subsystem ba‐ sis. The two forms can be combined (see the example below). The argument _subsys_ can take one of the following values: **general**, **proc**, **drive**, **media**, **inventory**, and **tree**. For example, to restore the root filesystem with tracing activated for all subsystems: **# xfsrestore -v trace -f /dev/tape /** To enable debug-level tracing for drive and media operations: **# xfsrestore -v drive=debug,media=debug -f /dev/tape /** To enable tracing for all subsystems, and debug level tracing for drive operations only: **# xfsrestore -v trace,drive=debug -f /dev/tape /** ### -A DMF environment this option should not be used. DMF stores file migration status within extended attributes associated with each file. If these attributes are not preserved when the filesystem is restored, files that had been in migrated state will not be re‐ callable by DMF. Note that dumping of extended file attributes is also optional. ### -B root directory of the dump. ### -D restored filesystem will be managed within the same DMF environment as the original dump it is essential that the -D option be used. Otherwise it is not usually desirable to re‐ store these settings. ### -E time of the on-media file is compared to the inode modification time of corresponding file in the _dest_ directory. The file is restored only if the on-media version is newer than the version in the _dest_ directory. The inode modification time of a file can be displayed with the **ls -lc **command. ### -F the operator for verification of the selected dump as the restore target and from prompting for any media change. ### -I _dump_ is used, an online inventory in _/var/lib/xfsdump/inventory_ is updated. This is used to determine the base for incremental dumps. It is also useful for manually iden‐ tifying a dump session to be restored (see the **-L **and **-S **options). Suboptions to filter the inventory display are described later. ### -J _xfsrestore_ opportunistically updates the online inventory when it encounters an on-media session inventory, but only if run with an effective user id of root and only if this option is not given. ### -K determined automatically, but this option is required on the first _xfsrestore_ invocation in the rare case that a cumulative restore begins with a format 3 (or newer) dump and will be followed by a format 2 dump. ### -L _ Specifies the label of the dump session to be restored. The source media is searched for this label. It is any arbitrary string up to 255 characters long. The label of the desired dump session can be copied from the inventory display produced by the **-I **option. ### -O _ Insert the options contained in _options_file_ into the beginning of the command line. The options are specified just as they would appear if typed into the command line. In addition, newline characters (\n) can be used as whitespace. The options are placed be‐ fore all options actually given on the command line, just after the command name. Only one **-O **option can be used. Recursive use is ignored. The destination directory cannot be specified in _options_file_. ### -Q around one specific pathological scenario. When restoring a dump session which was in‐ terrupted due to an EOM condition and no online session inventory is available, _xfsre‐_ _store_ cannot know when the restore of that dump session is complete. The operator is forced to interrupt the restore session. In that case, if the operator tries to subse‐ quently apply a resumed dump (using the **-r **option), _xfsrestore_ refuses to do so. The operator must tell _xfsrestore_ to consider the base restore complete by using this option when applying the resumed dump. ### -R pressing the terminal interrupt character (see [_stty_(1)](https://www.chedong.com/phpMan.php/man/stty/1/markdown)). Use this option to resume the restore. The **-a **and _destination_ options must be the same. ### -S _ Specifies the session UUID of the dump session to be restored. The source media is searched for this UUID. The UUID of the desired dump session can be copied from the in‐ ventory display produced by the **-I **option. ### -T changes. This dialogue normally times out if no response is supplied. This option pre‐ vents the timeout. ### -X _ Specifies a subtree to exclude. This is the converse of the **-s **option. Any number of **-X **options are allowed. Each subtree is specified as a pathname relative to the restore _dest_. If a directory is specified, the directory and all files beneath that directory are excluded. ### -Y _ Specify I/O buffer ring length. _xfsrestore_ uses a ring of input buffers to achieve max‐ imum throughput when restoring from tape drives. The default ring length is 3. How‐ ever, this is not currently enabled on Linux yet, making this option benign. **- **A lone **- **causes the standard input to be read as the source of the dump to be restored. Standard input can be a pipe from another utility (such as [_xfsdump_(8)](https://www.chedong.com/phpMan.php/man/xfsdump/8/markdown)) or a redirected file. This option cannot be used with the **-f **option. The **- **must follow all other op‐ tions, and precede the _dest_ specification. The dumped filesystem is restored into the _dest_ directory. There is no default; the _dest_ must be specified. ## NOTES ### Cumulative Restoration A base (level 0) dump and an ordered set of delta dumps can be sequentially restored, each on top of the previous, to reproduce the contents of the original filesystem at the time the last delta was produced. The operator invokes _xfsrestore_ once for each dump. The **-r **option must be specified. The _dest_ directory must be the same for all invocations. Each invocation leaves a directory named _xfsrestorehousekeeping_ in the _dest_ directory (however, see the **-a** option above). This directory contains the state information that must be communicated be‐ tween invocations. The operator must remove this directory after the last delta has been ap‐ plied. _xfsrestore_ also generates a directory named _orphanage_ in the _dest_ directory. _xfsrestore_ re‐ moves this directory after completing a simple restore. However, if _orphanage_ is not empty, it is not removed. This can happen if files present on the dump media are not referenced by any of the restored directories. The _orphanage_ has an entry for each such file. The entry name is the file's original inode number, a ".", and the file's generation count modulo 4096 (only the lower 12 bits of the generation count are used). _xfsrestore_ does not remove the _orphanage_ after cumulative restores. Like the _xfsrestore‐_ _housekeeping_ directory, the operator must remove it after applying all delta dumps. ### Media Management A dump consists of one or more media files contained on one or more media objects. A media file contains all or a portion of the filesystem dump. Large filesystems are broken up into multiple media files to minimize the impact of media dropouts, and to accommodate media ob‐ ject boundaries (end-of-media). A media object is any storage medium: a tape cartridge, a remote tape device (see [_rmt_(8)](https://www.chedong.com/phpMan.php/man/rmt/8/markdown)), a regular file, or the standard input (currently other removable media drives are not sup‐ ported). Tape cartridges can contain multiple media files, which are typically separated by (in tape parlance) file marks. If a dump spans multiple media objects, the restore must be‐ gin with the media object containing the first media file dumped. The operator is prompted when the next media object is needed. Media objects can contain more than one dump. The operator can select the desired dump by specifying the dump label (**-L **option), or by specifying the dump UUID (**-S **option). If nei‐ ther is specified, _xfsrestore_ scans the entire media object, prompting the operator as each dump session is encountered. The inventory display (**-I **option) is useful for identifying the media objects required. It is also useful for identifying a dump session. The session UUID can be copied from the in‐ ventory display to the **-S **option argument to unambiguously identify a dump session to be re‐ stored. Dumps placed in regular files or the standard output do not span multiple media objects, nor do they contain multiple dumps. ### Inventory Each dump session updates an inventory database in _/var/lib/xfsdump/inventory_. This database can be displayed by invoking _xfsrestore_ with the **-I **option. The display uses tabbed indenta‐ tion to present the inventory hierarchically. The first level is filesystem. The second level is session. The third level is media stream (currently only one stream is supported). The fourth level lists the media files sequentially composing the stream. The following suboptions are available to filter the display. ### -I depth=_ (where _n_ is 1, 2, or 3) limits the hierarchical depth of the display. When _n_ is 1, only the filesystem information from the inventory is displayed. When _n_ is 2, only filesystem and session information are displayed. When _n_ is 3, only filesystem, session and stream information are displayed. ### -I level=_ (where _n_ is the dump level) limits the display to dumps of that particular dump level. The display may be restricted to media files contained in a specific media object. ### -I mobjid=_ (where _value_ is a media ID) specifies the media object by its media ID. ### -I mobjlabel=_ (where _value_ is a media label) specifies the media object by its media label. Similarly, the display can be restricted to a specific filesystem. ### -I mnt=_ (that is, [hostname:]pathname), identifies the filesystem by mountpoint. Specifying the hostname is optional, but may be useful in a clustered environment where more than one host can be responsible for dumping a filesystem. ### -I fsid=_ identifies the filesystem by filesystem ID. ### -I dev=_ (that is, [hostname:]device_pathname) identifies the filesystem by device. As with the **mnt **filter, specifying the hostname is optional. More than one of these suboptions, separated by commas, may be specified at the same time to limit the display of the inventory to those dumps of interest. However, at most four subop‐ tions can be specified at once: one to constrain the display hierarchy depth, one to con‐ strain the dump level, one to constrain the media object, and one to constrain the filesys‐ tem. For example, **-I depth=1,mobjlabel="tape 1",mnt=host1:/test_mnt **would display only the filesystem information (depth=1) for those filesystems that were mounted on _host1:/test_mnt_ at the time of the dump, and only those filesystems dumped to the media object labeled "tape 1". Dump records may be removed (pruned) from the inventory using the _xfsinvutil_ program. An additional media file is placed at the end of each dump stream. This media file contains the inventory information for the current dump session. If the online inventory files in _/var/lib/xfsdump/inventory_ are missing information for the current dump session, then the in‐ ventory information in the media file is automatically added to the files in _/var/lib/xfs‐_ _dump/inventory._ If you wish to incorporate the inventory information from the media file without restoring any data, you may do so using the **-t **option: **# xfsrestore -t -f /dev/tape** This is useful to rebuild the inventory database if it is ever lost or corrupted. The only caveat is that _xfsrestore_ needs to read through the entire dump in order to reach the inven‐ tory media file. This could become time consuming for dump sessions with large media files. ### Media Errors _xfsdump_ is tolerant of media errors, but cannot do error correction. If a media error occurs in the body of a media file, the filesystem file represented at that point is lost. The bad portion of the media is skipped, and the restoration resumes at the next filesystem file af‐ ter the bad portion of the media. If a media error occurs in the beginning of the media file, the entire media file is lost. For this reason, large dumps are broken into a number of reasonably sized media files. The restore resumes with the next media file. ### Quotas When _xfsdump_ dumps a filesystem with user quotas, it creates a file in the root of the dump called _xfsdump_quotas_. _xfsrestore_ can restore this file like any other file included in the dump. This file can be processed by the restore command of [_xfs_quota_(8)](https://www.chedong.com/phpMan.php/man/xfsquota/8/markdown) to reactivate the quotas. However, the _xfsdump_quotas_ file contains information which may first require modi‐ fication; specifically the filesystem name and the user ids. If you are restoring the quotas for the same users on the same filesystem from which the dump was taken, then no modification will be necessary. However, if you are restoring the dump to a different filesystem, you will need to: - ensure the new filesystem is mounted with the quota option - modify the _xfsdump_quotas_ file to contain the new filesystem name - ensure the uids in the _xfsdump_quotas_ file are correct Once the quota information has been verified, the restore command of _xfs_quota_ [_(8)](https://www.chedong.com/phpMan.php/man//8/markdown)_ can be used to apply the quota limits to the filesystem. Group and project quotas are handled in a similar fashion and will be restored in files called _xfsdump_quotas_group_ and _xfsdump_quotas_proj_, respectively. ## EXAMPLES To restore the root filesystem from a locally mounted tape: **# xfsrestore -f /dev/tape /** To restore from a remote tape, specifying the dump session id: **# xfsrestore -L session_1 -f otherhost:/dev/tape /new** To restore the contents a of a dump to another subdirectory: **# xfsrestore -f /dev/tape /newdir** To copy the contents of a filesystem to another directory (see [_xfsdump_(8)](https://www.chedong.com/phpMan.php/man/xfsdump/8/markdown)): **# xfsdump -J - / | xfsrestore -J - /new** ## FILES /var/lib/xfsdump/inventory dump inventory database ## SEE ALSO [rmt(8)](https://www.chedong.com/phpMan.php/man/rmt/8/markdown), [xfsdump(8)](https://www.chedong.com/phpMan.php/man/xfsdump/8/markdown), [xfsinvutil(8)](https://www.chedong.com/phpMan.php/man/xfsinvutil/8/markdown), [xfs_quota(8)](https://www.chedong.com/phpMan.php/man/xfsquota/8/markdown), [attr_set(2)](https://www.chedong.com/phpMan.php/man/attrset/2/markdown). ## DIAGNOSTICS The exit code is 0 on normal completion, and non-zero if an error occurred or the restore was terminated by the operator. For all verbosity levels greater than 0 (**silent**) the final line of the output shows the exit status of the restore. It is of the form: **xfsdump: Restore Status: _**code_ Where _code_ takes one of the following values: **SUCCESS **(normal completion), **INTERRUPT **(inter‐ rupted), **QUIT **(media no longer usable), **INCOMPLETE **(restore incomplete), **FAULT **(software er‐ ror), and **ERROR **(resource error). Every attempt will be made to keep both the syntax and the semantics of this log message unchanged in future versions of xfsrestore. However, it may be necessary to refine or expand the set of exit codes, or their interpretation at some point in the future. ## BUGS Pathnames of restored non-directory files (relative to the _dest_ directory) must be 1023 char‐ acters (MAXPATHLEN) or less. Longer pathnames are discarded and a warning message displayed. There is no verify option to _xfsrestore_. This would allow the operator to compare a filesys‐ tem dump to an existing filesystem, without actually doing a restore. The interactive commands (**-i **option) do not understand regular expressions. When the minimal rmt option is specified, _xfsrestore_ applies it to all remote tape sources. The same blocksize (specified by the **-b **option) is used for all these remote drives. _xfsrestore_ uses the alert program only when a media change is required. Cumulative mode (**-r **option) requires that the operator invoke _xfsrestore_ for the base and for each delta to be applied in sequence to the base. It would be better to allow the operator to identify the last delta in the sequence of interest, and let _xfsrestore_ work backwards from that delta to identify and apply the preceding deltas and base dump, all in one invoca‐ tion. [_xfsrestore_(8)](https://www.chedong.com/phpMan.php/man/xfsrestore/8/markdown)