'\" t
.\"     Title: vfs_fileid
.\"    Author: [see the "AUTHOR" section]
.\" Generator: DocBook XSL Stylesheets v1.79.1 <http://docbook.sf.net/>
.\"      Date: 04/05/2019
.\"    Manual: System Administration tools
.\"    Source: Samba 4.5
.\"  Language: English
.\"
.TH "VFS_FILEID" "8" "04/05/2019" "Samba 4\&.5" "System Administration tools"
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.SH "NAME"
vfs_fileid \- Generates file_id structs with unique device id values for cluster setups
.SH "SYNOPSIS"
.HP \w'\ 'u
vfs objects = fileid
.SH "DESCRIPTION"
.PP
This VFS module is part of the
\fBsamba\fR(7)
suite\&.
.PP
Samba uses file_id structs to uniquely identify files for locking purpose\&. By default the file_id contains the device and inode number returned by the
stat()
system call\&. As the file_id is a unique identifier of a file, it must be the same on all nodes in a cluster setup\&. This module overloads the
SMB_VFS_FILE_ID_CREATE()
operation and generates the device number based on the configured algorithm (see the "fileid:algorithm" option)\&.
.SH "OPTIONS"
.PP
fileid:algorithm = ALGORITHM
.RS 4
Available algorithms are
fsname
and
fsid\&. The default value is
fsname\&.
.sp
The
fsname
algorithm generates device id by hashing the kernel device name\&.
.sp
The
fsid
algorithm generates the device id from the
f_fsid
returned from the
statfs()
syscall\&.
.RE
.PP
fileid:mapping = ALGORITHM
.RS 4
This option is the legacy version of the
fileid:algorithm
option, which was used in earlier versions of fileid mapping feature in custom Samba 3\&.0 versions\&.
.RE
.SH "EXAMPLES"
.PP
Usage of the
fileid
module with the
fsid
algorithm:
.sp
.if n \{\
.RS 4
.\}
.nf
        \fI[global]\fR
	\m[blue]\fBvfs objects = fileid\fR\m[]
	\m[blue]\fBfileid:algorithm = fsid\fR\m[]
.fi
.if n \{\
.RE
.\}
.SH "VERSION"
.PP
This man page is correct for version 3\&.2 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\&.