1.\" $OpenBSD: fsck.8,v 1.35 2023/01/04 13:00:11 jsg Exp $ 2.\" $NetBSD: fsck.8,v 1.14 1996/10/03 20:08:29 christos Exp $ 3.\" 4.\" Copyright (c) 1996 Christos Zoulas. All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 15.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25.\" 26.Dd $Mdocdate: January 4 2023 $ 27.Dt FSCK 8 28.Os 29.Sh NAME 30.Nm fsck 31.Nd file system consistency check and interactive repair 32.Sh SYNOPSIS 33.Nm fsck 34.Bk -words 35.Op Fl dfNnpvy 36.Op Fl b Ar block# 37.Op Fl l Ar maxparallel 38.Op Fl T Ar fstype : Ns Ar fsoptions 39.Op Fl t Ar fstype 40.Op Ar special | node ... 41.Ek 42.Sh DESCRIPTION 43The 44.Nm 45command invokes file-system-specific programs to check the 46special devices listed in the 47.Xr fstab 5 48file or on the command line for consistency. 49.Pp 50It is normally used in the script 51.Xr rc 8 52during automatic reboot. 53If no file systems are specified, 54.Nm 55reads the file 56.Xr fstab 5 57to determine which file systems to check and in what order. 58Only partitions in fstab that are mounted 59.Dq rw 60or 61.Dq ro 62and that have non-zero pass numbers are checked. 63File systems with pass number 1 (normally just the root file system) are 64checked one at a time. 65When pass 1 completes, all remaining file systems are checked, with one 66process spawned per disk drive. 67The disk drive containing each file system is inferred from the longest 68prefix of the device name that ends in a digit; the remaining characters 69are assumed to be the partition designator. 70By default, file systems which are already mounted read/write are not 71checked. 72.Pp 73The options are as follows: 74.Bl -tag -width Ds 75.It Fl b Ar block# 76Causes 77.Nm 78to use the specified block as the location of the superblock. 79Block 32 is usually an alternate super block. 80This option is only valid for filesystems that support backup superblocks 81(ffs and ext2fs). 82.It Fl d 83Debugging mode. 84Just print the commands without executing them. 85Available only if 86.Nm 87is compiled to support it. 88.It Fl f 89Force checking of file systems, even when they are marked clean (for file systems 90that support this). 91.It Fl l Ar maxparallel 92Limit the number of parallel checks to 93.Ar maxparallel . 94By default, the limit is the number of 95disks, running one process per disk. 96If a smaller limit is given, 97the disks are checked round-robin, one file system at a time. 98.It Fl N 99When using 100.Xr fstab 5 , 101only check filesystems that have the 102.Dq net 103mount option set. 104By default file systems with this option are ignored. 105.It Fl n 106Assume a 107.Dq no 108response to all questions asked by 109.Nm 110except for 111.Dq CONTINUE? , 112which is assumed to be affirmative. 113File systems will not be opened for writing. 114This is the default for file systems to be checked that are 115concurrently mounted writable. 116.It Fl p 117Enter preen mode: 118.Nm 119will check all file systems listed in 120.Xr fstab 5 121according to their pass number, 122or any special devices listed on the command line, 123and will make minor repairs without 124human intervention. 125Any major problems will cause 126.Nm 127to exit with a non-zero exit code, 128so as to alert any invoking program or script 129that human intervention is required. 130.It Fl T Ar fstype : Ns Ar fsoptions 131List of comma separated file system specific options for the specified 132file system type, in the same format as 133.Xr mount 8 . 134.It Fl t Ar fstype 135Invoke 136.Nm 137only for the comma separated list of file system types. 138If the list starts with 139.Dq no , 140invoke 141.Nm 142only in the file system types that are 143.Em not 144specified in 145the list. 146.It Fl v 147Print the commands before executing them. 148.It Fl y 149Cause 150.Nm 151to assume 152.Dq yes 153as the answer to all operator questions. 154.El 155.Pp 156If neither of the 157.Fl y 158or 159.Fl n 160options are specified, the user may force 161.Nm 162to assume an answer of 163.Dq yes 164to all the remaining questions by replying to a question with a value of 165.Dq F . 166.Sh FILES 167.Bl -tag -width /etc/fstab -compact 168.It Pa /etc/fstab 169file system table 170.El 171.Sh SEE ALSO 172.Xr fs 5 , 173.Xr fstab 5 , 174.Xr fsck_ext2fs 8 , 175.Xr fsck_ffs 8 , 176.Xr fsck_msdos 8 , 177.Xr fsdb 8 , 178.Xr growfs 8 , 179.Xr mount 8 , 180.Xr newfs 8 , 181.Xr rc 8 , 182.Xr scan_ffs 8 183