1.\" Copyright (c) 1980, 1989, 1991 The Regents of the University of California. 2.\" All rights reserved. 3.\" 4.\" %sccs.include.redist.roff% 5.\" 6.\" @(#)mount.8 6.16 (Berkeley) 05/04/91 7.\" 8.Dd 9.Dt MOUNT 8 10.Os BSD 4 11.Sh NAME 12.Nm mount , 13.Nm umount 14.Nd mount and dismount file systems 15.Sh SYNOPSIS 16.Nm mount 17.Op Fl afrwu 18.Op Fl t Ar nfs | ufs | external_type 19.Nm mount 20.Op Fl frwu 21.Ar special| node 22.Nm mount 23.Op Fl frwu 24.Op Fl t Ar nfs | ufs | external_type 25.Op | Ar external_type 26.Op Fl o Ar options 27.Ar special node 28.Nm umount 29.Op Fl af 30.Op Fl t Ar nfs | ufs | external_type 31.Nm umount 32.Op Fl f 33.Ar special | node 34.Sh DESCRIPTION 35The 36.Nm mount 37command 38calls the 39.Xr mount 2 40system call to prepare and graft a 41.Ar special 42device or the remote node 43(rhost:path) 44on to the file system tree at the point 45.Ar node. 46If either 47.Ar special 48or 49.Ar node 50are not provided, the appropriate 51information is taken from the 52.Xr fstab 5 53file. 54.Pp 55The system maintains a list of currently mounted file systems. 56If no arguments are given to 57.Nm mount, 58this list is printed. 59.Pp 60Options available for the 61.Nm mount 62command: 63.Bl -tag -width indent 64.It Fl F 65The standard mount options are parsed and 66passed to external program via the 67.Fl F 68option 69as a decimal number. 70(See example below.) 71.It Fl f 72Causes everything to be done except for the actual system call; if it's 73not obvious, this ``fakes'' mounting the file system. 74This option is useful in conjunction with the 75.Fl v 76flag to 77determine what the 78.Nm mount 79command is trying to do. 80.It Fl o 81Options are specified with a 82.Fl o 83flag 84followed by a comma separated string of options. 85The following options apply to any file system that is being mounted: 86.Bl -tag -width indent 87.It noexec 88Do not allow execution of any binaries on the mounted file system. 89This options is useful for a server that has file systems containing 90binaries for architectures other than its own. 91.It nosuid 92Do not allow set-user-identifier or set-group-identifier bits to take effect. 93.It nodev 94Do not interpret character or block special devices on the file system. 95This options is useful for a server that has file systems containing 96special devices for architectures other than its own. 97.It synchronous 98All I/O to the file system should be done synchronously. 99.El 100.It Fl r 101The file system object is to be mounted read-only. 102.It Fl t Ar "nfs \\*(Ba ufs \\*(Ba external type" 103The argument following the 104.Fl t 105is used to indicate the file system type. 106The type 107.Ar ufs 108is the default. 109For example, the 110.Nm mount 111command: 112.Bd -literal -offset indent 113mount -a -t nonfs,mfs 114.Ed 115.Pp 116mounts all filesystems except those of type 117.Tn NFS 118and 119.Tn MFS . 120.Pp 121If the type is not one of the internally known types, 122mount will attempt to execute a program in 123.Pa /sbin/mount_ Ns Em XXX 124where 125.Em XXX 126is replaced by the type name. 127.It Fl u 128The 129.Fl u 130flag indicates that the status of an already mounted file 131system should be changed. 132Any of the options discussed above (the 133.Fl o 134option) 135may be changed; 136also a file system can be changed from read-only to read-write. 137The set of options is determined by first extracting the options 138for the file system from the 139.Xr fstab 140table, 141then applying any options specified by the 142.Fl o 143argument, 144and finally applying the 145.Fl r 146or 147.Fl w 148option. 149.It Fl v 150Verbose mode. 151.It Fl w 152The file system object is to be read and write. 153.It Fl 154Any additional options specific to the program can 155be passed as a comma separated list; 156these options are distinguished by starting with a 157.Fl 158(dash). 159.El 160.Pp 161Those options that take a value are specified 162using the syntax -option=value. 163For example, the mount command: 164.Bd -literal -offset indent 165mount -t mfs -o nosuid,-N,-s=4000 /dev/dk0b /tmp 166.Ed 167.Pp 168causes mount to attempt to execute: 169.Bd -literal -offset indent 170/sbin/mount_mfs -F 8 -N -s 4000 /dev/dk0b /tmp 171.Ed 172.Pp 173The following list can be used to override 174the defaults for an nfs mount: 175.Bl -tag -width indent 176.It hard 177.Tn I/O 178system calls will retry until the server responds (default) 179.It soft 180.Tn I/O 181system calls will fail and return errno after 182.Em retrans 183request 184retransmissions 185.It spongy 186Soft semantics for the stat, lookup, fsstat, readlink and readdir 187filesystem operations and hard semantics for the others. 188This option is meant to be similar to hard, 189except that processes will not be hung forever when 190they trip over mount points to dead servers. 191.It bg 192If the first mount request times out, do retries in background 193.It intr 194.Tn I/O 195system calls can be interrupted. 196.It noconn 197Do not connect the socket. 198Used for 199.Tn UDP 200servers that send replies from a 201socket other than the nfs server socket. 202.It tcp 203Use 204.Tn TCP 205transport instead of 206.Tn UDP . 207.It rsize=# 208Set read size to 209.Ar # 210bytes. 211.It wsize=# 212Set write size to 213.Ar # 214bytes. 215.It retry=# 216Set mount retry count to 217.Ar # . 218.It retrans=# 219Set retransmission count for nfs rpc's to 220.Ar # . 221.It timeo=# 222Set initial nfs timeout to 223.Ar # 224in 0.1 sec intervals. 225.El 226.Pp 227.Nm Umount 228removes the 229.Ar special 230device 231grafted 232at point 233.Ar node 234from file system tree. 235.Pp 236Options for the 237.Nm umount 238command: 239.Bl -tag -width indent 240.It Fl f 241The file system is forcibly unmounted. 242Active special devices continue to work, 243but all other files return errors if further accesses are attempted. 244The root file system cannot be forcibly unmounted. 245.It Fl a 246All of the file systems described in 247.Xr fstab 248are unmounted. 249.It Fl t 250Is used to indicate the actions should only be taken on 251filesystems of the specified type. 252More than one type may be specified in a comma separated list. 253The list of filesystem types can be prefixed with ``no'' to 254specify the filesystem types on which no action should be taken. 255(See example above for the 256.Nm mount 257command.) 258.El 259.Sh FILES 260.Bl -tag -width /etc/fstab -compact 261.It Pa /etc/fstab 262file system table 263.El 264.Sh SEE ALSO 265.Xr mount 2 , 266.Xr unmount 2 , 267.Xr fstab 5 268.Sh BUGS 269It is possible for a corrupted file system to cause a crash. 270.Sh HISTORY 271A 272.Nm 273command appeared in 274.At v6 . 275