samba/docs/manpages/vfs_btrfs.8

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.\" Title: vfs_btrfs
.\" Author: [see the "AUTHOR" section]
.\" Generator: DocBook XSL Stylesheets v1.79.1 <http://docbook.sf.net/>
.\" Date: 01/28/2020
.\" Manual: System Administration tools
.\" Source: Samba 4.11.6
.\" Language: English
.\"
.TH "VFS_BTRFS" "8" "01/28/2020" "Samba 4\&.11\&.6" "System Administration tools"
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.SH "NAME"
vfs_btrfs \- Utilize features provided by the Btrfs filesystem
.SH "SYNOPSIS"
.HP \w'\ 'u
vfs objects = btrfs
.SH "DESCRIPTION"
.PP
This VFS module is part of the
\fBsamba\fR(8)
suite\&.
.PP
The
vfs_btrfs
VFS module exposes Btrfs specific features for use by Samba\&.
.PP
Btrfs allows for multiple files to share the same on\-disk data through the use cloned ranges\&. When an SMB client issues a request to copy duplicate data (via FSCTL_SRV_COPYCHUNK), this module maps the request to a Btrfs clone range IOCTL, instead of performing reads and writes required by a traditional copy\&. Doing so saves storage capacity and greatly reduces disk IO\&.
.PP
This module also exposes Btrfs per\-file compression support to SMB clients via the get/set compression fsctls\&.
.PP
Btrfs snapshots can be manipulated by Samba\*(Aqs FSRVP server\&. Snapshot manipulation using this module is currently considered experimental, and is therefore disabled by default\&. The
vfs_snapper
module is instead recommended for this purpose\&.
.PP
This module is stackable\&.
.SH "OPTIONS"
.PP
btrfs: manipulate snapshots = [yes|no]
.RS 4
When set to
\fIyes\fR, experimental support for the creation and deletion of snapshots via corresponding Btrfs IOCTLs will be enabled\&. The default is
\fIno\fR, which means that such requests are passed through to any underlying VFS module\&.
.RE
.SH "CONFIGURATION"
.PP
vfs_btrfs
requires that the underlying share path is a Btrfs subvolume\&.
.sp
.if n \{\
.RS 4
.\}
.nf
\fI[share]\fR
\m[blue]\fBvfs objects = btrfs\fR\m[]
\m[blue]\fBbtrfs: manipulate snapshots = no\fR\m[]
.fi
.if n \{\
.RE
.\}
.PP
To use the experimental snapshot manipulation functionality provided by this module, it must be explicitly enabled, and Samba\*(Aqs FSRVP server must be running\&.
.PP
The
vfs_shadow_copy
module can be used to expose snapshots created by
vfs_btrfs
to Windows Explorer as file / directory "previous versions"\&.
.sp
.if n \{\
.RS 4
.\}
.nf
\fI[global]\fR
\m[blue]\fBrpc_daemon:fssd = fork\fR\m[]
\m[blue]\fBregistry shares = yes\fR\m[]
\m[blue]\fBinclude = registry\fR\m[]
\fI[share]\fR
\m[blue]\fBvfs objects = btrfs shadow_copy\fR\m[]
\m[blue]\fBbtrfs: manipulate snapshots = yes\fR\m[]
.fi
.if n \{\
.RE
.\}
.SH "VERSION"
.PP
This man page is part of version 4\&.11\&.6 of the Samba suite\&.
.SH "AUTHOR"
.PP
The original Samba software and related utilities were created by Andrew Tridgell\&. Samba is now developed by the Samba Team as an Open Source project similar to the way the Linux kernel is developed\&.