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.\" @(#)mount.8 8.8 (Berkeley) 6/16/94 33.\" $FreeBSD: src/sbin/mount/mount.8,v 1.31.2.12 2003/02/23 21:17:42 trhodes Exp $ 34.\" 35.Dd October 7, 2011 36.Dt MOUNT_UFS 8 37.Os 38.Sh NAME 39.Nm mount_ufs 40.Nd mount file systems 41.Sh SYNOPSIS 42.Nm 43.Op Fl adfpruvw 44.Op Fl F Ar fstab 45.Op Fl o Ar options 46.Op Fl t Ar type 47.Nm 48.Op Fl dfpruvw 49.Brq Ar special | node 50.Nm 51.Op Fl dfpruvw 52.Op Fl o Ar options 53.Op Fl t Ar type 54.Ar special node 55.Sh DESCRIPTION 56The 57.Nm 58utility calls the 59.Xr mount 2 60system call to prepare and graft a 61.Ar "special device" 62or the remote node (rhost:path) on to the file system tree at the point 63.Ar node . 64If either 65.Ar special 66or 67.Ar node 68are not provided, the appropriate information is taken from the 69.Xr fstab 5 70file. 71.Pp 72The system maintains a list of currently mounted file systems. 73If no arguments are given to 74.Nm , 75this list is printed. 76.Pp 77The options are as follows: 78.Bl -tag -width indent 79.It Fl a 80All the filesystems described in 81.Xr fstab 5 82are mounted. 83Exceptions are those marked as 84.Dq noauto , 85excluded by the 86.Fl t 87flag (see below), or if they are already mounted (except the 88root filesystem which is always remounted to preserve 89traditional single user mode behavior). 90.It Fl d 91Causes everything to be done except for the actual system call. 92This option is useful in conjunction with the 93.Fl v 94flag to 95determine what the 96.Nm 97command is trying to do. 98.It Fl F Ar fstab 99Specify the 100.Pa fstab 101file to use. 102.It Fl f 103Forces the revocation of write access when trying to downgrade 104a filesystem mount status from read-write to read-only. 105Also 106forces the R/W mount of an unclean filesystem (dangerous; use with 107caution). 108.It Fl o 109Options are specified with a 110.Fl o 111flag followed by a comma separated string of options. 112If a 113.Dq no 114prefix is added or removed from a option name, then meaning is negated. 115In case of conflicting options being specified, the rightmost option 116takes effect. 117The following options are available: 118.Bl -tag -width indent 119.It Cm async 120All 121.Tn I/O 122to the file system should be done asynchronously. 123This is a 124.Em dangerous 125flag to set, 126and should not be used unless you are prepared to recreate the file 127system should your system crash. 128.It Cm current 129When used with the 130.Fl u 131flag, this is the same as specifying the options currently in effect for 132the mounted filesystem. 133.It Cm force 134The same as 135.Fl f ; 136forces the revocation of write access when trying to downgrade 137a filesystem mount status from read-write to read-only. 138Also 139forces the R/W mount of an unclean filesystem (dangerous; use with caution). 140.It Cm fstab 141When used with the 142.Fl u 143flag, this is the same as specifying all the options listed in the 144.Xr fstab 5 145file for the filesystem. 146.It Cm noasync 147Metadata I/O should be done synchronously, while data I/O should be done 148asynchronously. 149This is the default. 150.It Cm noatime 151Do not update the file access time when reading from a file. 152This option 153is useful on filesystems where there are large numbers of files and 154performance is more critical than updating the file access time (which is 155rarely ever important). 156This option is currently only supported on local filesystems. 157.It Cm noauto 158This filesystem should be skipped when 159.Nm 160is run with the 161.Fl a 162flag. 163.It Cm noclusterr 164Disable read clustering. 165.It Cm noclusterw 166Disable write clustering. 167.It Cm nodev 168Do not interpret character or block special devices on the file system. 169This option is useful for a server that has file systems containing 170special devices for architectures other than its own. 171This option is set automatically when the user does not have super-user 172privileges. 173.It Cm noexec 174Do not allow execution of any binaries on the mounted file system. 175This option is useful for a server that has file systems containing 176binaries for architectures other than its own. 177.It Cm nosuid 178Do not allow set-user-identifier or set-group-identifier bits to take effect. 179Note: this option is worthless if a public available suid or sgid 180wrapper like 181.Xr suidperl 1 182is installed on your system. 183It is set automatically when the user does not have super-user privileges. 184.It Cm nosymfollow 185Do not follow symlinks 186on the mounted file system. 187.It Cm rdonly , ro , norw 188The same as 189.Fl r ; 190mount the file system read-only (even the super-user may not write it). 191.It Cm sync 192All 193.Tn I/O 194to the file system should be done synchronously. 195.It Cm trim 196If the device supports TRIM 197.Va ( kern.cam.da.X.trim_enabled 198exists) and is set, 199the file system will perform online trim for corresponding block deletions. 200Currently, only 201.Xr UFS 5 202supports this feature. 203.It Cm suiddir 204A directory on the mounted filesystem will respond to the SUID bit 205being set, by setting the owner of any new files to be the same 206as the owner of the directory. 207New directories will inherit the bit from their parents. 208Execute bits are removed from 209the file, and it will not be given to root. 210.Pp 211This feature is designed for use on fileservers serving PC users via 212ftp or SAMBA. 213It provides security holes for shell users and as 214such should not be used on shell machines, especially on home directories. 215This option requires the SUIDDIR 216option in the kernel to work. 217Only 218.Xr UFS 5 219filesystems support this option. 220See 221.Xr chmod 2 222for more information. 223.It Cm update 224The same as 225.Fl u ; 226indicate that the status of an already mounted file system should be changed. 227.It Cm union 228Causes the namespace at the mount point to appear as the union 229of the mounted filesystem root and the existing directory. 230Lookups will be done in the mounted filesystem first. 231If those operations fail due to a non-existent file the underlying 232directory is then accessed. 233All creates are done in the mounted filesystem. 234.It Cm ignore 235Will be ignored by 236.Xr df 1 . 237.El 238.Pp 239Any additional options specific to a filesystem type that is not 240one of the internally known types (see the 241.Fl t 242option) may be passed as a comma separated list; these options are 243distinguished by a leading 244.Dq \&- 245(dash). 246Options that take a value are specified using the syntax -option=value. 247For example, the 248.Nm 249command: 250.Bd -literal -offset indent 251mount -t mfs -o nosuid,-N,-s=4000 /dev/da0s0b /tmp 252.Ed 253.Pp 254causes 255.Nm 256to execute the equivalent of: 257.Bd -literal -offset indent 258/sbin/mount_mfs -o nosuid -N -s 4000 /dev/da0s0b /tmp 259.Ed 260.Pp 261Additional options specific to filesystem types 262which are not internally known 263(see the description of the 264.Fl t 265option below) 266may be described in the manual pages for the associated 267.Pa /sbin/mount_ Ns Sy XXX 268utilities. 269.It Fl p 270Print mount information in 271.Xr fstab 5 272format. 273If fstab is missing or if the freq and passno fields are omitted, 274the default values as described in 275.Xr fstab 5 276are used. 277Implies also the 278.Fl v 279option. 280.It Fl r 281The file system is to be mounted read-only. 282Mount the file system read-only (even the super-user may not write it). 283The same as the 284.Cm rdonly 285argument to the 286.Fl o 287option. 288.It Fl t Ar type 289The argument following the 290.Fl t 291is used to indicate the file system type. 292The type 293.Cm ufs 294is the default. 295The 296.Fl t 297option can be used 298to indicate that the actions should only be taken on 299filesystems of the specified type. 300More than one type may be specified in a comma separated list. 301The list of filesystem types can be prefixed with 302.Dq no 303to specify the filesystem types for which action should 304.Em not 305be taken. 306For example, the 307.Nm 308command: 309.Bd -literal -offset indent 310mount -a -t nonfs,mfs 311.Ed 312.Pp 313mounts all filesystems except those of type 314.Tn NFS 315and 316.Tn MFS . 317.Pp 318If the type is not the internally known type, 319.Cm ufs , 320.Nm 321will attempt to execute a program in 322.Pa /sbin/mount_ Ns Sy XXX 323where 324.Sy XXX 325is replaced by the type name. 326For example, nfs filesystems are mounted by the program 327.Pa /sbin/mount_nfs . 328.Pp 329Most filesystems will be dynamically loaded by their 330.Nm 331programs 332if not already present in the kernel, using the 333.Xr vfsload 3 334subroutine. 335Because this mechanism requires writable temporary space, 336the filesystem type containing 337.Pa /tmp 338must be compiled into the kernel, and the filesystems containing 339.Pa /tmp 340and 341.Pa /usr/bin/ld 342must be listed in 343.Pa /etc/fstab 344before any filesystems which might be dynamically loaded. 345.It Fl u 346The 347.Fl u 348flag indicates that the status of an already mounted file 349system should be changed. 350Any of the options discussed above (the 351.Fl o 352option) 353may be changed; 354also a file system can be changed from read-only to read-write 355or vice versa. 356An attempt to change from read-write to read-only will fail if any 357files on the filesystem are currently open for writing unless the 358.Fl f 359flag is also specified. 360The set of options is determined by applying the options specified 361in the argument to 362.Fl o 363and finally applying the 364.Fl r 365or 366.Fl w 367option. 368.It Fl v 369Verbose mode. 370.It Fl w 371The file system object is to be read and write. 372.El 373.Sh ENVIRONMENT 374.Bl -tag -width PATH_FSTAB 375.It Pa PATH_FSTAB 376If the environment variable 377.Pa PATH_FSTAB 378is set all operations are performed against the specified file. 379.El 380.Sh FILES 381.Bl -tag -width /etc/fstab -compact 382.It Pa /etc/fstab 383file system table 384.El 385.Sh DIAGNOSTICS 386Various, most of them are self-explanatory. 387.Pp 388.Dl XXXXX filesystem is not available 389.Pp 390The kernel does not support the respective filesystem type. 391Note that 392support for a particular filesystem might be provided either on a static 393(kernel compile-time), or dynamic basis (loaded as a kernel module by 394.Xr kldload 8 ) . 395Normally, 396.Nm 397or its subprocesses attempt to dynamically load a filesystem module if 398it has not been configured statically, using 399.Xr vfsload 3 . 400In this case, the above error message can also mean that you did not 401have permission to load the module. 402.Sh SEE ALSO 403.Xr df 1 , 404.Xr lsvfs 1 , 405.Xr mount 2 , 406.Xr vfsload 3 , 407.Xr devtab 5 , 408.Xr fstab 5 , 409.Xr UFS 5 , 410.Xr kldload 8 , 411.Xr mount_cd9660 8 , 412.Xr mount_devfs 8 , 413.Xr mount_ext2fs 8 , 414.Xr mount_fdesc 8 , 415.Xr mount_hammer 8 , 416.Xr mount_hpfs 8 , 417.Xr mount_linprocfs 8 , 418.Xr mount_mfs 8 , 419.Xr mount_msdos 8 , 420.Xr mount_nfs 8 , 421.Xr mount_ntfs 8 , 422.Xr mount_null 8 , 423.Xr mount_nwfs 8 , 424.Xr mount_portal 8 , 425.Xr mount_procfs 8 , 426.Xr mount_smbfs 8 , 427.Xr mount_std 8 , 428.Xr mount_tmpfs 8 , 429.Xr mount_udf 8 , 430.Xr mount_union 8 , 431.Xr sysctl 8 , 432.Xr umount 8 433.Sh HISTORY 434A 435.Nm 436utility appeared in 437.At v1 . 438.Sh CAVEATS 439After a successful 440.Nm , 441the permissions on the original mount point determine if 442.Pa ..\& 443is accessible from the mounted file system. 444The minimum permissions for 445the mount point for traversal across the mount point in both 446directions to be possible for all users is 0111 (execute for all). 447.Sh BUGS 448It is possible for a corrupted file system to cause a crash. 449