1.\" $NetBSD: fsck_ext2fs.8,v 1.12 2003/08/07 10:04:16 agc Exp $ 2.\" 3.\" Copyright (c) 1980, 1989, 1991, 1993 4.\" The Regents of the University of California. 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.\" 3. Neither the name of the University nor the names of its contributors 15.\" may be used to endorse or promote products derived from this software 16.\" without specific prior written permission. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 19.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 22.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28.\" SUCH DAMAGE. 29.\" 30.\" Copyright (c) 1997 Manuel Bouyer. 31.\" 32.\" Redistribution and use in source and binary forms, with or without 33.\" modification, are permitted provided that the following conditions 34.\" are met: 35.\" 1. Redistributions of source code must retain the above copyright 36.\" notice, this list of conditions and the following disclaimer. 37.\" 2. Redistributions in binary form must reproduce the above copyright 38.\" notice, this list of conditions and the following disclaimer in the 39.\" documentation and/or other materials provided with the distribution. 40.\" 3. All advertising materials mentioning features or use of this software 41.\" must display the following acknowledgement: 42.\" This product includes software developed by the University of 43.\" California, Berkeley and its contributors. 44.\" 4. Neither the name of the University nor the names of its contributors 45.\" may be used to endorse or promote products derived from this software 46.\" without specific prior written permission. 47.\" 48.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 49.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 50.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 51.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 52.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 53.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 54.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 55.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 56.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 57.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 58.\" SUCH DAMAGE. 59.\" 60.\" @(#)fsck.8 8.3 (Berkeley) 11/29/94 61.\" 62.Dd November 29, 1994 63.Dt FSCK_EXT2FS 8 64.Os 65.Sh NAME 66.Nm fsck_ext2fs 67.Nd EXT2 File System consistency check and interactive repair 68.Sh SYNOPSIS 69.Nm 70.Op Fl b Ar block# 71.Op Fl c Ar level 72.Op Fl d 73.Op Fl f 74.Op Fl m Ar mode 75.Op Fl p 76.Op Fl y 77.Op Fl n 78.Ar filesystem ... 79.Sh DESCRIPTION 80.Nm 81performs interactive filesystem consistency checks and repair for each of 82the filesystems specified on the command line. 83It is normally invoked from 84.Xr fsck 8 . 85.Pp 86The kernel takes care that only a restricted class of innocuous filesystem 87inconsistencies can happen unless hardware or software failures intervene. 88These are limited to the following: 89.Pp 90.Bl -item -compact 91.It 92Unreferenced inodes 93.It 94Link counts in inodes too large 95.It 96Missing blocks in the free map 97.It 98Blocks in the free map also in files 99.It 100Counts in the super-block wrong 101.El 102.Pp 103These are the only inconsistencies that 104.Nm 105in ``preen'' 106mode (with the 107.Fl p 108option) will correct; if it encounters other inconsistencies, it exits 109with an abnormal return status. 110For each corrected inconsistency one or more lines will be printed 111identifying the filesystem on which the correction will take place, 112and the nature of the correction. 113After successfully correcting a filesystem, 114.Nm 115will print the number of files on that filesystem 116and the number of used and free blocks. 117.Pp 118If sent a 119.Dv QUIT 120signal, 121.Nm 122will finish the filesystem checks, then exit with an abnormal return status. 123.Pp 124Without the 125.Fl p 126option, 127.Nm 128audits and interactively repairs inconsistent conditions for filesystems. 129If the filesystem is inconsistent the operator is prompted for concurrence 130before each correction is attempted. 131It should be noted that some of the corrective actions which are not 132correctable under the 133.Fl p 134option will result in some loss of data. 135The amount and severity of data lost may be determined from the diagnostic 136output. 137The default action for each consistency correction 138is to wait for the operator to respond 139.Li yes 140or 141.Li no . 142If the operator does not have write permission on the filesystem 143.Nm 144will default to a 145.Fl n 146action. 147.Pp 148The following flags are interpreted by 149.Nm . 150.Bl -tag -width indent 151.It Fl b 152Use the block specified immediately after the flag as 153the super block for the filesystem. 154Block 8193 is usually an alternate super block. 155.It Fl d 156Print debugging output. 157.It Fl f 158Force checking of file systems. 159Normally, if a file system is cleanly unmounted, the kernel will set a 160.Dq clean flag 161in the file system superblock, and 162.Nm 163will not check the file system. 164This option forces 165.Nm 166to check the file system, regardless of the state of the clean flag. 167.It Fl m 168Use the mode specified in octal immediately after the flag as the 169permission bits to use when creating the 170.Pa lost+found 171directory rather than the default 1777. 172In particular, systems that do not wish to have lost files accessible 173by all users on the system should use a more restrictive 174set of permissions such as 700. 175.It Fl n 176Assume a no response to all questions asked by 177.Nm 178except for 179.Ql CONTINUE? , 180which is assumed to be affirmative; 181do not open the filesystem for writing. 182.It Fl p 183Specify ``preen'' mode, described above. 184.It Fl y 185Assume a yes response to all questions asked by 186.Nm ; 187this should be used with great caution as this is a free license 188to continue after essentially unlimited trouble has been encountered. 189.El 190.Pp 191.Bl -enum -offset indent -compact 192Inconsistencies checked are as follows: 193.It 194Blocks claimed by more than one inode or the free map. 195.It 196Blocks claimed by an inode outside the range of the filesystem. 197.It 198Incorrect link counts. 199.It 200Size checks: 201.Bl -item -offset indent -compact 202.It 203Directory size not a multiple of filesystem block size. 204.It 205Partially truncated file. 206.El 207.It 208Bad inode format. 209.It 210Blocks not accounted for anywhere. 211.It 212Directory checks: 213.Bl -item -offset indent -compact 214.It 215File pointing to unallocated inode. 216.It 217Inode number out of range. 218.It 219Dot or dot-dot not the first two entries of a directory 220or having the wrong inode number. 221.El 222.It 223Super Block checks: 224.Bl -item -offset indent -compact 225.It 226More blocks for inodes than there are in the filesystem. 227.It 228Bad free block map format. 229.It 230Total free block and/or free inode count incorrect. 231.El 232.El 233.Pp 234Orphaned files and directories (allocated but unreferenced) are, 235with the operator's concurrence, reconnected by 236placing them in the 237.Pa lost+found 238directory. 239The name assigned is the inode number. 240If the 241.Pa lost+found 242directory does not exist, it is created. 243If there is insufficient space its size is increased. 244.Pp 245Because of inconsistencies between the block device and the buffer cache, 246the raw device should always be used. 247.Sh DIAGNOSTICS 248The diagnostics produced by 249.Nm 250are fully enumerated and explained in Appendix A of 251.Rs 252.%T "Fsck \- The UNIX File System Check Program" 253.Re 254.Sh SEE ALSO 255.Xr fs 5 , 256.Xr fstab 5 , 257.Xr fsck 8 , 258.Xr fsdb 8 , 259.Xr newfs 8 , 260.Xr reboot 8 261