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. Neither the name of the University nor the names of its contributors 13.\" may be used to endorse or promote products derived from this software 14.\" without specific prior written permission. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.\" @(#)mount.8 8.8 (Berkeley) 6/16/94 29.\" $FreeBSD: src/sbin/mount/mount.8,v 1.31.2.12 2003/02/23 21:17:42 trhodes Exp $ 30.\" 31.Dd October 7, 2011 32.Dt MOUNT_UFS 8 33.Os 34.Sh NAME 35.Nm mount_ufs 36.Nd mount file systems 37.Sh SYNOPSIS 38.Nm 39.Op Fl adfpruvw 40.Op Fl F Ar fstab 41.Op Fl o Ar options 42.Op Fl t Ar type 43.Nm 44.Op Fl dfpruvw 45.Brq Ar special | node 46.Nm 47.Op Fl dfpruvw 48.Op Fl o Ar options 49.Op Fl t Ar type 50.Ar special node 51.Sh DESCRIPTION 52The 53.Nm 54utility calls the 55.Xr mount 2 56system call to prepare and graft a 57.Ar "special device" 58or the remote node (rhost:path) on to the file system tree at the point 59.Ar node . 60If either 61.Ar special 62or 63.Ar node 64are not provided, the appropriate information is taken from the 65.Xr fstab 5 66file. 67.Pp 68The system maintains a list of currently mounted file systems. 69If no arguments are given to 70.Nm , 71this list is printed. 72.Pp 73The options are as follows: 74.Bl -tag -width indent 75.It Fl a 76All the filesystems described in 77.Xr fstab 5 78are mounted. 79Exceptions are those marked as 80.Dq noauto , 81excluded by the 82.Fl t 83flag (see below), or if they are already mounted (except the 84root filesystem which is always remounted to preserve 85traditional single user mode behavior). 86.It Fl d 87Causes everything to be done except for the actual system call. 88This option is useful in conjunction with the 89.Fl v 90flag to 91determine what the 92.Nm 93command is trying to do. 94.It Fl F Ar fstab 95Specify the 96.Pa fstab 97file to use. 98.It Fl f 99Forces the revocation of write access when trying to downgrade 100a filesystem mount status from read-write to read-only. 101Also 102forces the R/W mount of an unclean filesystem (dangerous; use with 103caution). 104.It Fl o 105Options are specified with a 106.Fl o 107flag followed by a comma separated string of options. 108If a 109.Dq no 110prefix is added or removed from a option name, then meaning is negated. 111In case of conflicting options being specified, the rightmost option 112takes effect. 113The following options are available: 114.Bl -tag -width indent 115.It Cm async 116All 117.Tn I/O 118to the file system should be done asynchronously. 119This is a 120.Em dangerous 121flag to set, 122and should not be used unless you are prepared to recreate the file 123system should your system crash. 124.It Cm current 125When used with the 126.Fl u 127flag, this is the same as specifying the options currently in effect for 128the mounted filesystem. 129.It Cm force 130The same as 131.Fl f ; 132forces the revocation of write access when trying to downgrade 133a filesystem mount status from read-write to read-only. 134Also 135forces the R/W mount of an unclean filesystem (dangerous; use with caution). 136.It Cm fstab 137When used with the 138.Fl u 139flag, this is the same as specifying all the options listed in the 140.Xr fstab 5 141file for the filesystem. 142.It Cm noasync 143Metadata I/O should be done synchronously, while data I/O should be done 144asynchronously. 145This is the default. 146.It Cm noatime 147Do not update the file access time when reading from a file. 148This option 149is useful on filesystems where there are large numbers of files and 150performance is more critical than updating the file access time (which is 151rarely ever important). 152This option is currently only supported on local filesystems. 153.It Cm noauto 154This filesystem should be skipped when 155.Nm 156is run with the 157.Fl a 158flag. 159.It Cm noclusterr 160Disable read clustering. 161.It Cm noclusterw 162Disable write clustering. 163.It Cm nodev 164Do not interpret character or block special devices on the file system. 165This option is useful for a server that has file systems containing 166special devices for architectures other than its own. 167This option is set automatically when the user does not have super-user 168privileges. 169.It Cm noexec 170Do not allow execution of any binaries on the mounted file system. 171This option is useful for a server that has file systems containing 172binaries for architectures other than its own. 173.It Cm nosuid 174Do not allow set-user-identifier or set-group-identifier bits to take effect. 175Note: this option is worthless if a public available suid or sgid 176wrapper like 177.Xr suidperl 1 178is installed on your system. 179It is set automatically when the user does not have super-user privileges. 180.It Cm nosymfollow 181Do not follow symlinks 182on the mounted file system. 183.It Cm rdonly , ro , norw 184The same as 185.Fl r ; 186mount the file system read-only (even the super-user may not write it). 187.It Cm sync 188All 189.Tn I/O 190to the file system should be done synchronously. 191.It Cm trim 192If the device supports TRIM 193.Va ( kern.cam.da.X.trim_enabled 194exists) and is set, 195the file system will perform online trim for corresponding block deletions. 196Currently, only 197.Xr UFS 5 198supports this feature. 199.It Cm suiddir 200A directory on the mounted filesystem will respond to the SUID bit 201being set, by setting the owner of any new files to be the same 202as the owner of the directory. 203New directories will inherit the bit from their parents. 204Execute bits are removed from 205the file, and it will not be given to root. 206.Pp 207This feature is designed for use on fileservers serving PC users via 208ftp or SAMBA. 209It provides security holes for shell users and as 210such should not be used on shell machines, especially on home directories. 211This option requires the SUIDDIR 212option in the kernel to work. 213Only 214.Xr UFS 5 215filesystems support this option. 216See 217.Xr chmod 2 218for more information. 219.It Cm update 220The same as 221.Fl u ; 222indicate that the status of an already mounted file system should be changed. 223.It Cm union 224Causes the namespace at the mount point to appear as the union 225of the mounted filesystem root and the existing directory. 226Lookups will be done in the mounted filesystem first. 227If those operations fail due to a non-existent file the underlying 228directory is then accessed. 229All creates are done in the mounted filesystem. 230.It Cm ignore 231Will be ignored by 232.Xr df 1 . 233.El 234.Pp 235Any additional options specific to a filesystem type that is not 236one of the internally known types (see the 237.Fl t 238option) may be passed as a comma separated list; these options are 239distinguished by a leading 240.Dq \&- 241(dash). 242Options that take a value are specified using the syntax -option=value. 243For example, the 244.Nm 245command: 246.Bd -literal -offset indent 247mount -t mfs -o nosuid,-N,-s=4000 /dev/da0s0b /tmp 248.Ed 249.Pp 250causes 251.Nm 252to execute the equivalent of: 253.Bd -literal -offset indent 254/sbin/mount_mfs -o nosuid -N -s 4000 /dev/da0s0b /tmp 255.Ed 256.Pp 257Additional options specific to filesystem types 258which are not internally known 259(see the description of the 260.Fl t 261option below) 262may be described in the manual pages for the associated 263.Pa /sbin/mount_ Ns Sy XXX 264utilities. 265.It Fl p 266Print mount information in 267.Xr fstab 5 268format. 269If fstab is missing or if the freq and passno fields are omitted, 270the default values as described in 271.Xr fstab 5 272are used. 273Implies also the 274.Fl v 275option. 276.It Fl r 277The file system is to be mounted read-only. 278Mount the file system read-only (even the super-user may not write it). 279The same as the 280.Cm rdonly 281argument to the 282.Fl o 283option. 284.It Fl t Ar type 285The argument following the 286.Fl t 287is used to indicate the file system type. 288The type 289.Cm ufs 290is the default. 291The 292.Fl t 293option can be used 294to indicate that the actions should only be taken on 295filesystems of the specified type. 296More than one type may be specified in a comma separated list. 297The list of filesystem types can be prefixed with 298.Dq no 299to specify the filesystem types for which action should 300.Em not 301be taken. 302For example, the 303.Nm 304command: 305.Bd -literal -offset indent 306mount -a -t nonfs,mfs 307.Ed 308.Pp 309mounts all filesystems except those of type 310.Tn NFS 311and 312.Tn MFS . 313.Pp 314If the type is not the internally known type, 315.Cm ufs , 316.Nm 317will attempt to execute a program in 318.Pa /sbin/mount_ Ns Sy XXX 319where 320.Sy XXX 321is replaced by the type name. 322For example, nfs filesystems are mounted by the program 323.Pa /sbin/mount_nfs . 324.Pp 325Most filesystems will be dynamically loaded by their 326.Nm 327programs 328if not already present in the kernel, using the 329.Xr vfsload 3 330subroutine. 331Because this mechanism requires writable temporary space, 332the filesystem type containing 333.Pa /tmp 334must be compiled into the kernel, and the filesystems containing 335.Pa /tmp 336and 337.Pa /usr/bin/ld 338must be listed in 339.Pa /etc/fstab 340before any filesystems which might be dynamically loaded. 341.It Fl u 342The 343.Fl u 344flag indicates that the status of an already mounted file 345system should be changed. 346Any of the options discussed above (the 347.Fl o 348option) 349may be changed; 350also a file system can be changed from read-only to read-write 351or vice versa. 352An attempt to change from read-write to read-only will fail if any 353files on the filesystem are currently open for writing unless the 354.Fl f 355flag is also specified. 356The set of options is determined by applying the options specified 357in the argument to 358.Fl o 359and finally applying the 360.Fl r 361or 362.Fl w 363option. 364.It Fl v 365Verbose mode. 366.It Fl w 367The file system object is to be read and write. 368.El 369.Sh ENVIRONMENT 370.Bl -tag -width PATH_FSTAB 371.It Pa PATH_FSTAB 372If the environment variable 373.Pa PATH_FSTAB 374is set all operations are performed against the specified file. 375.El 376.Sh FILES 377.Bl -tag -width /etc/fstab -compact 378.It Pa /etc/fstab 379file system table 380.El 381.Sh DIAGNOSTICS 382Various, most of them are self-explanatory. 383.Pp 384.Dl XXXXX filesystem is not available 385.Pp 386The kernel does not support the respective filesystem type. 387Note that 388support for a particular filesystem might be provided either on a static 389(kernel compile-time), or dynamic basis (loaded as a kernel module by 390.Xr kldload 8 ) . 391Normally, 392.Nm 393or its subprocesses attempt to dynamically load a filesystem module if 394it has not been configured statically, using 395.Xr vfsload 3 . 396In this case, the above error message can also mean that you did not 397have permission to load the module. 398.Sh SEE ALSO 399.Xr df 1 , 400.Xr lsvfs 1 , 401.Xr mount 2 , 402.Xr vfsload 3 , 403.Xr devtab 5 , 404.Xr fstab 5 , 405.Xr UFS 5 , 406.Xr kldload 8 , 407.Xr mount_cd9660 8 , 408.Xr mount_devfs 8 , 409.Xr mount_ext2fs 8 , 410.Xr mount_fdesc 8 , 411.Xr mount_hammer 8 , 412.Xr mount_hpfs 8 , 413.Xr mount_linprocfs 8 , 414.Xr mount_mfs 8 , 415.Xr mount_msdos 8 , 416.Xr mount_nfs 8 , 417.Xr mount_ntfs 8 , 418.Xr mount_null 8 , 419.Xr mount_nwfs 8 , 420.Xr mount_portal 8 , 421.Xr mount_procfs 8 , 422.Xr mount_smbfs 8 , 423.Xr mount_std 8 , 424.Xr mount_tmpfs 8 , 425.Xr mount_udf 8 , 426.Xr mount_union 8 , 427.Xr sysctl 8 , 428.Xr umount 8 429.Sh HISTORY 430A 431.Nm 432utility appeared in 433.At v1 . 434.Sh CAVEATS 435After a successful 436.Nm , 437the permissions on the original mount point determine if 438.Pa ..\& 439is accessible from the mounted file system. 440The minimum permissions for 441the mount point for traversal across the mount point in both 442directions to be possible for all users is 0111 (execute for all). 443.Sh BUGS 444It is possible for a corrupted file system to cause a crash. 445