1.\" 2.\" Copyright (c) 1980, 1989, 1991, 1993 3.\" The Regents of the University of California. All rights reserved. 4.\" 5.\" Redistribution and use in source and binary forms, with or without 6.\" modification, are permitted provided that the following conditions 7.\" are met: 8.\" 1. Redistributions of source code must retain the above copyright 9.\" notice, this list of conditions and the following disclaimer. 10.\" 2. Redistributions in binary form must reproduce the above copyright 11.\" notice, this list of conditions and the following disclaimer in the 12.\" documentation and/or other materials provided with the distribution. 13.\" 4. Neither the name of the University nor the names of its contributors 14.\" may be used to endorse or promote products derived from this software 15.\" without specific prior written permission. 16.\" 17.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27.\" SUCH DAMAGE. 28.\" 29.\" @(#)fsck.8 8.4 (Berkeley) 5/9/95 30.\" $FreeBSD$ 31.\" 32.Dd April 24, 2001 33.Dt FSCK_FFS 8 34.Os 35.Sh NAME 36.Nm fsck_ffs , 37.Nm fsck_ufs 38.Nd file system consistency check and interactive repair 39.Sh SYNOPSIS 40.Nm 41.Op Fl BFpfny 42.Op Fl b Ar block 43.Op Fl c Ar level 44.Op Fl m Ar mode 45.Ar filesystem 46.Ar ... 47.Sh DESCRIPTION 48The specified disk partitions and/or file systems are checked. 49In "preen" mode the clean flag of each file system's superblock is examined 50and only those file systems that 51are not marked clean are checked. 52File systems are marked clean when they are unmounted, 53when they have been mounted read-only, or when 54.Nm 55runs on them successfully. 56If the 57.Fl f 58option is specified, the file systems 59will be checked regardless of the state of their clean flag. 60.Pp 61The kernel takes care that only a restricted class of innocuous file system 62inconsistencies can happen unless hardware or software failures intervene. 63These are limited to the following: 64.Pp 65.Bl -item -compact -offset indent 66.It 67Unreferenced inodes 68.It 69Link counts in inodes too large 70.It 71Missing blocks in the free map 72.It 73Blocks in the free map also in files 74.It 75Counts in the super-block wrong 76.El 77.Pp 78These are the only inconsistencies that 79.Nm 80with the 81.Fl p 82option will correct; if it encounters other inconsistencies, it exits 83with an abnormal return status and an automatic reboot will then fail. 84For each corrected inconsistency one or more lines will be printed 85identifying the file system on which the correction will take place, 86and the nature of the correction. 87After successfully correcting a file system, 88.Nm 89will print the number of files on that file system, 90the number of used and free blocks, 91and the percentage of fragmentation. 92.Pp 93If sent a 94.Dv QUIT 95signal, 96.Nm 97will finish the file system checks, then exit with an abnormal 98return status that causes an automatic reboot to fail. 99This is useful when you want to finish the file system checks during an 100automatic reboot, 101but do not want the machine to come up multiuser after the checks complete. 102.Pp 103If 104.Nm 105receives a 106.Dv SIGINFO 107(see the 108.Dq status 109argument for 110.Xr stty 1 ) 111signal, a line will be written to the standard output indicating 112the name of the device currently being checked, the current phase 113number and phase-specific progress information. 114.Pp 115Without the 116.Fl p 117option, 118.Nm 119audits and interactively repairs inconsistent conditions for file systems. 120If the file system is inconsistent the operator is prompted for concurrence 121before each correction is attempted. 122It should be noted that some of the corrective actions which are not 123correctable under the 124.Fl p 125option will result in some loss of data. 126The amount and severity of data lost may be determined from the diagnostic 127output. 128The default action for each consistency correction 129is to wait for the operator to respond 130.Li yes 131or 132.Li no . 133If the operator does not have write permission on the file system 134.Nm 135will default to a 136.Fl n 137action. 138.Pp 139The following flags are interpreted by 140.Nm : 141.Bl -tag -width indent 142.It Fl F 143Determine whether the file system needs to be cleaned immediately 144in foreground, or if its cleaning can be deferred to background. 145To be eligible for background cleaning it must have been running 146with soft updates, not have been marked as needing a foreground check, 147and be mounted and writable when the background check is to be done. 148If these conditions are met, then 149.Nm 150exits with a zero exit status. 151Otherwise it exits with a non-zero exit status. 152If the file system is clean, 153it will exit with a non-zero exit status so that the clean status 154of the file system can be verified and reported during the foreground 155checks. 156Note that when invoked with the 157.Fl F 158flag, no cleanups are done. 159The only thing that 160.Nm 161does is to determine whether a foreground or background 162check is needed and exit with an appropriate status code. 163.It Fl B 164A check is done on the specified and possibly active file system. 165The set of corrections that can be done is limited to those done 166when running in preen mode (see the 167.Fl p 168flag). 169If unexpected errors are found, 170the file system is marked as needing a foreground check and 171.Nm 172exits without attempting any further cleaning. 173.It Fl b 174Use the block specified immediately after the flag as 175the super block for the file system. 176An alternate super block is usually located at block 32 for UFS1, 177and block 160 for UFS2. 178.It Fl c 179Convert the file system to the specified level. 180Note that the level of a file system can only be raised. 181There are currently four levels defined: 182.Bl -tag -width indent 183.It 0 184The file system is in the old (static table) format. 185.It 1 186The file system is in the new (dynamic table) format. 187.It 2 188The file system supports 32-bit uid's and gid's, 189short symbolic links are stored in the inode, 190and directories have an added field showing the file type. 191.It 3 192If maxcontig is greater than one, 193build the free segment maps to aid in finding contiguous sets of blocks. 194If maxcontig is equal to one, delete any existing segment maps. 195.El 196.Pp 197In interactive mode, 198.Nm 199will list the conversion to be made 200and ask whether the conversion should be done. 201If a negative answer is given, 202no further operations are done on the file system. 203In preen mode, 204the conversion is listed and done if 205possible without user interaction. 206Conversion in preen mode is best used when all the file systems 207are being converted at once. 208The format of a file system can be determined from the 209first line of output from 210.Xr dumpfs 8 . 211.It Fl f 212Force 213.Nm 214to check 215.Sq clean 216file systems when preening. 217.It Fl m 218Use the mode specified in octal immediately after the flag as the 219permission bits to use when creating the 220.Pa lost+found 221directory rather than the default 1777. 222In particular, systems that do not wish to have lost files accessible 223by all users on the system should use a more restrictive 224set of permissions such as 700. 225.It Fl n 226Assume a no response to all questions asked by 227.Nm 228except for 229.Ql CONTINUE? , 230which is assumed to be affirmative; 231do not open the file system for writing. 232.It Fl p 233Preen file systems (see above). 234.It Fl y 235Assume a yes response to all questions asked by 236.Nm ; 237this should be used with great caution as this is a free license 238to continue after essentially unlimited trouble has been encountered. 239.El 240.Pp 241Inconsistencies checked are as follows: 242.Pp 243.Bl -enum -compact 244.It 245Blocks claimed by more than one inode or the free map. 246.It 247Blocks claimed by an inode outside the range of the file system. 248.It 249Incorrect link counts. 250.It 251Size checks: 252.Bl -item -offset indent -compact 253.It 254Directory size not a multiple of DIRBLKSIZ. 255.It 256Partially truncated file. 257.El 258.It 259Bad inode format. 260.It 261Blocks not accounted for anywhere. 262.It 263Directory checks: 264.Bl -item -offset indent -compact 265.It 266File pointing to unallocated inode. 267.It 268Inode number out of range. 269.It 270Directories with unallocated blocks (holes). 271.It 272Dot or dot-dot not the first two entries of a directory 273or having the wrong inode number. 274.El 275.It 276Super Block checks: 277.Bl -item -offset indent -compact 278.It 279More blocks for inodes than there are in the file system. 280.It 281Bad free block map format. 282.It 283Total free block and/or free inode count incorrect. 284.El 285.El 286.Pp 287Orphaned files and directories (allocated but unreferenced) are, 288with the operator's concurrence, reconnected by 289placing them in the 290.Pa lost+found 291directory. 292The name assigned is the inode number. 293If the 294.Pa lost+found 295directory does not exist, it is created. 296If there is insufficient space its size is increased. 297.Sh FILES 298.Bl -tag -width /etc/fstab -compact 299.It Pa /etc/fstab 300contains default list of file systems to check. 301.El 302.Sh EXIT STATUS 303.Ex -std 304.Sh DIAGNOSTICS 305The diagnostics produced by 306.Nm 307are fully enumerated and explained in Appendix A of 308.Rs 309.%T "Fsck \- The UNIX File System Check Program" 310.Re 311.Sh SEE ALSO 312.Xr fs 5 , 313.Xr fstab 5 , 314.Xr fsck 8 , 315.Xr fsdb 8 , 316.Xr newfs 8 , 317.Xr reboot 8 318