1.\" Copyright (c) 1980, 1989, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. All advertising materials mentioning features or use of this software 13.\" must display the following acknowledgement: 14.\" This product includes software developed by the University of 15.\" California, Berkeley and its contributors. 16.\" 4. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)fstab.5 8.1 (Berkeley) 6/5/93 33.\" $FreeBSD$ 34.\" 35.Dd June 5, 1993 36.Dt FSTAB 5 37.Os 38.Sh NAME 39.Nm fstab 40.Nd static information about the file systems 41.Sh SYNOPSIS 42.In fstab.h 43.Sh DESCRIPTION 44The file 45.Nm 46contains descriptive information about the various file 47systems. 48.Nm 49is only read by programs, and not written; 50it is the duty of the system administrator to properly create 51and maintain this file. 52Each file system is described on a separate line; 53fields on each line are separated by tabs or spaces. 54The order of records in 55.Nm 56is important because 57.Xr fsck 8 , 58.Xr mount 8 , 59and 60.Xr umount 8 61sequentially iterate through 62.Nm 63doing their thing. 64.Pp 65The first field, 66.Pq Fa fs_spec , 67describes the block special device or 68remote file system to be mounted. 69For file systems of type 70.Em ufs , 71the special file name is the block special file name, 72and not the character special file name. 73If a program needs the character special file name, 74the program must create it by appending a ``r'' after the 75last ``/'' in the special file name. 76.Pp 77The second field, 78.Pq Fa fs_file , 79describes the mount point for the file system. 80For swap partitions, this field should be specified as ``none''. 81.Pp 82The third field, 83.Pq Fa fs_vfstype , 84describes the type of the file system. 85The system can support various file system types. 86Only the root, /usr, and /tmp file systems need be statically 87compiled into the kernel; 88everything else will be automatically loaded at mount 89time. 90(Exception: the UFS family - FFS and LFS cannot 91currently be demand-loaded.) 92Some people still prefer to statically 93compile other file systems as well. 94.Pp 95The fourth field, 96.Pq Fa fs_mntops , 97describes the mount options associated with the file system. 98It is formatted as a comma separated list of options. 99It contains at least the type of mount (see 100.Fa fs_type 101below) plus any additional options 102appropriate to the file system type. 103See the options flag 104.Pq Fl o 105in the 106.Xr mount 8 107page and the file system specific page, such as 108.Xr mount_nfs 8 , 109for additional options that may be specified. 110.Pp 111If the options ``userquota'' and/or ``groupquota'' are specified, 112the file system is automatically processed by the 113.Xr quotacheck 8 114command, and user and/or group disk quotas are enabled with 115.Xr quotaon 8 . 116By default, 117file system quotas are maintained in files named 118.Pa quota.user 119and 120.Pa quota.group 121which are located at the root of the associated file system. 122These defaults may be overridden by putting an equal sign 123and an alternative absolute pathname following the quota option. 124Thus, if the user quota file for 125.Pa /tmp 126is stored in 127.Pa /var/quotas/tmp.user , 128this location can be specified as: 129.Bd -literal -offset indent 130userquota=/var/quotas/tmp.user 131.Ed 132.Pp 133If the option ``noauto'' is specified, the file system will not be automatically 134mounted at system startup. 135Note that, for network file systems 136of third party types 137(i.e., types supported by additional software 138not included in the base system) 139to be automatically mounted at system startup, 140the 141.Va extra_netfs_types 142.Xr rc.conf 5 143variable must be used to extend the 144.Xr rc 8 145startup script's list of network file system types. 146.Pp 147The type of the mount is extracted from the 148.Fa fs_mntops 149field and stored separately in the 150.Fa fs_type 151field (it is not deleted from the 152.Fa fs_mntops 153field). 154If 155.Fa fs_type 156is ``rw'' or ``ro'' then the file system whose name is given in the 157.Fa fs_file 158field is normally mounted read-write or read-only on the 159specified special file. 160If 161.Fa fs_type 162is ``sw'' then the special file is made available as a piece of swap 163space by the 164.Xr swapon 8 165command at the end of the system reboot procedure. 166The fields other than 167.Fa fs_spec 168and 169.Fa fs_type 170are unused. 171If 172.Fa fs_type 173is specified as ``xx'' the entry is ignored. 174This is useful to show disk partitions which are currently unused. 175.Pp 176The fifth field, 177.Pq Fa fs_freq , 178is used for these file systems by the 179.Xr dump 8 180command to determine which file systems need to be dumped. 181If the fifth field is not present, a value of zero is returned and 182.Nm dump 183will assume that the file system does not need to be dumped. 184.Pp 185The sixth field, 186.Pq Fa fs_passno , 187is used by the 188.Xr fsck 8 189and 190.Xr quotacheck 8 191programs to determine the order in which file system checks are done 192at reboot time. 193The root file system should be specified with a 194.Fa fs_passno 195of 1, and other file systems should have a 196.Fa fs_passno 197of 2. 198File systems within a drive will be checked sequentially, 199but file systems on different drives will be checked at the 200same time to utilize parallelism available in the hardware. 201If the sixth field is not present or is zero, 202a value of zero is returned and 203.Xr fsck 8 204and 205.Xr quotacheck 8 206will assume that the file system does not need to be checked. 207.Bd -literal 208#define FSTAB_RW "rw" /* read/write device */ 209#define FSTAB_RQ "rq" /* read/write with quotas */ 210#define FSTAB_RO "ro" /* read-only device */ 211#define FSTAB_SW "sw" /* swap device */ 212#define FSTAB_XX "xx" /* ignore totally */ 213 214struct fstab { 215 char *fs_spec; /* block special device name */ 216 char *fs_file; /* file system path prefix */ 217 char *fs_vfstype; /* File system type, ufs, nfs */ 218 char *fs_mntops; /* Mount options ala -o */ 219 char *fs_type; /* FSTAB_* from fs_mntops */ 220 int fs_freq; /* dump frequency, in days */ 221 int fs_passno; /* pass number on parallel fsck */ 222}; 223.Ed 224.Pp 225The proper way to read records from 226.Pa fstab 227is to use the routines 228.Xr getfsent 3 , 229.Xr getfsspec 3 , 230.Xr getfstype 3 , 231and 232.Xr getfsfile 3 . 233.Sh FILES 234.Bl -tag -width /etc/fstab -compact 235.It Pa /etc/fstab 236The file 237.Nm 238resides in 239.Pa /etc . 240.El 241.Sh SEE ALSO 242.Xr getfsent 3 , 243.Xr getvfsbyname 3 , 244.Xr dump 8 , 245.Xr fsck 8 , 246.Xr mount 8 , 247.Xr quotacheck 8 , 248.Xr quotaon 8 , 249.Xr swapon 8 , 250.Xr umount 8 251.Sh HISTORY 252The 253.Nm 254file format appeared in 255.Bx 4.0 . 256