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'\" t
.\"     Title: btrfs-image
.\"    Author: [FIXME: author] [see http://www.docbook.org/tdg5/en/html/author]
.\" Generator: DocBook XSL Stylesheets vsnapshot <http://docbook.sf.net/>
.\"      Date: 12/05/2018
.\"    Manual: Btrfs Manual
.\"    Source: Btrfs v4.19.1
.\"  Language: English
.\"
.TH "BTRFS\-IMAGE" "8" "12/05/2018" "Btrfs v4\&.19\&.1" "Btrfs Manual"
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.SH "NAME"
btrfs-image \- create/restore an image of the filesystem
.SH "SYNOPSIS"
.sp
\fBbtrfs\-image\fR [options] \fI<source>\fR \fI<target>\fR
.SH "DESCRIPTION"
.sp
\fBbtrfs\-image\fR is used to create an image of a btrfs filesystem\&. All data will be zeroed, but metadata and the like is preserved\&. Mainly used for debugging purposes\&.
.sp
In the dump mode, source is the btrfs device/file and target is the output file (use \fI\-\fR for stdout)\&.
.sp
In the restore mode (option \-r), source is the dumped image and target is the btrfs device/file\&.
.SH "OPTIONS"
.PP
\-r
.RS 4
Restore metadump image\&. By default, this fixes super\(cqs chunk tree, by using 1 stripe pointing to primary device, so that file system can be restored by running tree log reply if possible\&. To restore without changing number of stripes in chunk tree check \-o option\&.
.RE
.PP
\-c \fI<value>\fR
.RS 4
Compression level (0 ~ 9)\&.
.RE
.PP
\-t \fI<value>\fR
.RS 4
Number of threads (1 ~ 32) to be used to process the image dump or restore\&.
.RE
.PP
\-o
.RS 4
Use the old restore method, this does not fixup the chunk tree so the restored file system will not be able to be mounted\&.
.RE
.PP
\-s
.RS 4
Sanitize the file names when generating the image\&. One \-s means just generate random garbage, which means that the directory indexes won\(cqt match up since the hashes won\(cqt match with the garbage filenames\&. Using \-ss will calculate a collision for the filename so that the hashes match, and if it can\(cqt calculate a collision then it will just generate garbage\&. The collision calculator is very time and CPU intensive so only use it if you are having problems with your file system tree and need to have it mostly working\&.
.RE
.PP
\-w
.RS 4
Walk all the trees manually and copy any blocks that are referenced\&. Use this option if your extent tree is corrupted to make sure that all of the metadata is captured\&.
.RE
.PP
\-m
.RS 4
Restore for multiple devices, more than 1 device should be provided\&.
.RE
.SH "EXIT STATUS"
.sp
\fBbtrfs\-image\fR will return 0 if no error happened\&. If any problems happened, 1 will be returned\&.
.SH "SEE ALSO"
.sp
\fBmkfs\&.btrfs\fR(8)