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Diffstat (limited to 'sbin/fsck/fsck.8')
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diff --git a/sbin/fsck/fsck.8 b/sbin/fsck/fsck.8 new file mode 100644 index 00000000000..727f2767679 --- /dev/null +++ b/sbin/fsck/fsck.8 @@ -0,0 +1,308 @@ +.\" $NetBSD: fsck.8,v 1.10 1995/07/12 01:49:16 cgd Exp $ +.\" +.\" Copyright (c) 1980, 1989, 1991, 1993 +.\" The Regents of the University of California. All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" 3. All advertising materials mentioning features or use of this software +.\" must display the following acknowledgement: +.\" This product includes software developed by the University of +.\" California, Berkeley and its contributors. +.\" 4. Neither the name of the University nor the names of its contributors +.\" may be used to endorse or promote products derived from this software +.\" without specific prior written permission. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.\" @(#)fsck.8 8.3 (Berkeley) 11/29/94 +.\" +.Dd November 29, 1994 +.Dt FSCK 8 +.Os BSD 4 +.Sh NAME +.Nm fsck +.Nd filesystem consistency check and interactive repair +.Sh SYNOPSIS +.Nm fsck +.Fl p +.Op Fl f +.Op Fl m Ar mode +.Nm fsck +.Op Fl f +.Op Fl b Ar block# +.Op Fl c Ar level +.Op Fl l Ar maxparallel +.Op Fl y +.Op Fl n +.Op Fl m Ar mode +.Op Ar filesystem +.Ar ... +.Sh DESCRIPTION +The first form of +.Nm fsck +preens a standard set of filesystems or the specified filesystems. +It is normally used in the script +.Pa /etc/rc +during automatic reboot. +Here +.Nm fsck +reads the table +.Pa /etc/fstab +to determine which filesystems to check. +Only partitions in fstab that are mounted ``rw,'' ``rq'' or ``ro'' +and that have non-zero pass number are checked. +Filesystems with pass number 1 (normally just the root filesystem) +are checked one at a time. +When pass 1 completes, all remaining filesystems are checked, +running one process per disk drive. +The disk drive containing each filesystem is inferred from the longest prefix +of the device name that ends in a digit; the remaining characters are assumed +to be the partition designator. +.Pp +The kernel takes care that only a restricted class of innocuous filesystem +inconsistencies can happen unless hardware or software failures intervene. +These are limited to the following: +.Bl -item -compact +.It +Unreferenced inodes +.It +Link counts in inodes too large +.It +Missing blocks in the free map +.It +Blocks in the free map also in files +.It +Counts in the super-block wrong +.El +.Pp +These are the only inconsistencies that +.Nm fsck +with the +.Fl p +option will correct; if it encounters other inconsistencies, it exits +with an abnormal return status and an automatic reboot will then fail. +For each corrected inconsistency one or more lines will be printed +identifying the filesystem on which the correction will take place, +and the nature of the correction. After successfully correcting a filesystem, +.Nm fsck +will print the number of files on that filesystem, +the number of used and free blocks, +and the percentage of fragmentation. +.Pp +If sent a +.Dv QUIT +signal, +.Nm fsck +will finish the filesystem checks, then exit with an abnormal +return status that causes an automatic reboot to fail. +This is useful when you want to finish the filesystem checks during an +automatic reboot, +but do not want the machine to come up multiuser after the checks complete. +.Pp +Without the +.Fl p +option, +.Nm fsck +audits and interactively repairs inconsistent conditions for filesystems. +If the filesystem is inconsistent the operator is prompted for concurrence +before each correction is attempted. +It should be noted that some of the corrective actions which are not +correctable under the +.Fl p +option will result in some loss of data. +The amount and severity of data lost may be determined from the diagnostic +output. +The default action for each consistency correction +is to wait for the operator to respond +.Li yes +or +.Li no . +If the operator does not have write permission on the filesystem +.Nm fsck +will default to a +.Fl n +action. +.Pp +.Nm Fsck +has more consistency checks than +its predecessors +.Em check , dcheck , fcheck , +and +.Em icheck +combined. +.Pp +The following flags are interpreted by +.Nm fsck . +.Bl -tag -width indent +.It Fl f +Force checking of file systems. Normally, if a file system is cleanly +unmounted, the kernel will set a +.Dq clean flag +in the file system superblock, and +.Nm +will not check the file system. This option forces +.Nm +to check the file system, regardless of the state of the clean flag. +.It Fl b +Use the block specified immediately after the flag as +the super block for the filesystem. Block 32 is usually +an alternate super block. +.It Fl l +Limit the number of parallel checks to the number specified in the following +argument. +By default, the limit is the number of disks, running one process per disk. +If a smaller limit is given, the disks are checked round-robin, one filesystem +at a time. +.It Fl m +Use the mode specified in octal immediately after the flag as the +permission bits to use when creating the +.Pa lost+found +directory rather than the default 1777. +In particular, systems that do not wish to have lost files accessible +by all users on the system should use a more restrictive +set of permissions such as 700. +.It Fl y +Assume a yes response to all questions asked by +.Nm fsck ; +this should be used with great caution as this is a free license +to continue after essentially unlimited trouble has been encountered. +.It Fl n +Assume a no response to all questions asked by +.Nm fsck +except for +.Ql CONTINUE? , +which is assumed to be affirmative; +do not open the filesystem for writing. +.It Fl c +Convert the filesystem to the specified level. +Note that the level of a filesystem can only be raised. +.Bl -tag -width indent +There are currently four levels defined: +.It 0 +The filesystem is in the old (static table) format. +.It 1 +The filesystem is in the new (dynamic table) format. +.It 2 +The filesystem supports 32-bit uid's and gid's, +short symbolic links are stored in the inode, +and directories have an added field showing the file type. +.It 3 +If maxcontig is greater than one, +build the free segment maps to aid in finding contiguous sets of blocks. +If maxcontig is equal to one, delete any existing segment maps. +.El +.Pp +In interactive mode, +.Nm fsck +will list the conversion to be made +and ask whether the conversion should be done. +If a negative answer is given, +no further operations are done on the filesystem. +In preen mode, +the conversion is listed and done if +possible without user interaction. +Conversion in preen mode is best used when all the filesystems +are being converted at once. +The format of a filesystem can be determined from the +first line of output from +.Xr dumpfs 8 . +.El +.Pp +If no filesystems are given to +.Nm fsck +then a default list of filesystems is read from +the file +.Pa /etc/fstab . +.Pp +.Bl -enum -indent indent -compact +Inconsistencies checked are as follows: +.It +Blocks claimed by more than one inode or the free map. +.It +Blocks claimed by an inode outside the range of the filesystem. +.It +Incorrect link counts. +.It +Size checks: +.Bl -item -indent indent -compact +.It +Directory size not a multiple of DIRBLKSIZ. +.It +Partially truncated file. +.El +.It +Bad inode format. +.It +Blocks not accounted for anywhere. +.It +Directory checks: +.Bl -item -indent indent -compact +.It +File pointing to unallocated inode. +.It +Inode number out of range. +.It +Dot or dot-dot not the first two entries of a directory +or having the wrong inode number. +.El +.It +Super Block checks: +.Bl -item -indent indent -compact +.It +More blocks for inodes than there are in the filesystem. +.It +Bad free block map format. +.It +Total free block and/or free inode count incorrect. +.El +.El +.Pp +Orphaned files and directories (allocated but unreferenced) are, +with the operator's concurrence, reconnected by +placing them in the +.Pa lost+found +directory. +The name assigned is the inode number. +If the +.Pa lost+found +directory does not exist, it is created. +If there is insufficient space its size is increased. +.Pp +Because of inconsistencies between the block device and the buffer cache, +the raw device should always be used. +.Sh FILES +.Bl -tag -width /etc/fstab -compact +.It Pa /etc/fstab +contains default list of filesystems to check. +.El +.Sh DIAGNOSTICS +The diagnostics produced by +.Nm fsck +are fully enumerated and explained in Appendix A of +.Rs +.%T "Fsck \- The UNIX File System Check Program" +.Re +.Sh SEE ALSO +.Xr fstab 5 , +.Xr fs 5 , +.Xr fsdb 8 , +.Xr newfs 8 , +.Xr mkfs 8 , +.Xr reboot 8 |