1.\" Copyright (c) 2006 Ulrich Spoerlein <uspoerlein@gmail.com> 2.\" All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 13.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 14.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 17.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23.\" SUCH DAMAGE. 24.\" 25.\" $FreeBSD$ 26.\" 27.Dd May 6, 2006 28.Dt RECOVERDISK 1 29.Os 30.Sh NAME 31.Nm recoverdisk 32.Nd recover data from hard disk or optical media 33.Sh SYNOPSIS 34.Nm 35.Op Fl b Ar bigsize 36.Op Fl r Ar rlist 37.Op Fl s Ar snapshot 38.Op Fl w Ar wlist 39.Ar special 40.Op Ar file 41.Sh DESCRIPTION 42The 43.Nm 44utility reads data from the 45.Ar special 46file until all blocks could be successfully read. 47It starts reading in multiples of the sector size. 48Whenever a block fails, it is put to the end of the working queue and will be 49read again, possibly with a smaller read size. 50.Pp 51By default it uses block sizes of roughly 1 MB, 32kB, and the native 52sector size (usually 512 bytes). 53These figures are adjusted slightly, for devices whose sectorsize is not a 54power of 2, e.g., audio CDs with a sector size of 2352 bytes. 55.Pp 56The options are as follows: 57.Bl -tag -width indent 58.It Fl b Ar bigsize 59The size of reads attempted first. 60The middle pass is roughly the logarithmic average of the bigsize and 61the sectorsize. 62.It Fl r Ar rlist 63Read the list of blocks and block sizes to read from the specified file. 64.It Fl s Ar snapshot 65How often we should update the worklist file while things go OK. 66The default is 60 and the units is "progress messages" so if things 67go well, this is the same as once per minute. 68.It Fl w Ar wlist 69Write the list of remaining blocks to read to the specified file if 70.Nm 71is aborted via 72.Dv SIGINT . 73.El 74.Pp 75The 76.Fl r 77and 78.Fl w 79options can be specified together. 80Especially, they can point to the same file, which will be updated on abort. 81.Sh OUTPUT 82The 83.Nm 84utility 85prints several columns, detailing the progress 86.Bl -tag -width remaining 87.It Va start 88Starting offset of the current block. 89.It Va size 90Read size of the current block. 91.It Va len 92Length of the current block. 93.It Va state 94Is increased for every failed read. 95.It Va done 96Number of bytes already read. 97.It Va remaining 98Number of bytes remaining. 99.It Va "% done" 100Percent complete. 101.El 102.Sh EXAMPLES 103.Bd -literal 104# recover data from failing hard drive ad3 105touch /data/lots_of_space 106recoverdisk /dev/ad3 /data/lots_of_space 107 108# clone a hard disk 109recoverdisk /dev/ad3 /dev/ad4 110 111# read an ISO image from a CD-ROM 112touch /data/cd.iso; recoverdisk /dev/acd0 /data/cd.iso 113 114# continue reading from a broken CD and update the existing worklist 115recoverdisk -r worklist -w worklist /dev/acd0 /data/cd.iso 116 117# recover a single file from the unreadable media 118touch file.avi; recoverdisk /cdrom/file.avi file.avi 119 120# If the disk hangs the system on read-errors try: 121recoverdisk -b 0 /dev/ad3 /somewhere 122 123.Ed 124.Sh SEE ALSO 125.Xr dd 1 126.Sh HISTORY 127The 128.Nm 129utility first appeared in 130.Fx 7.0 . 131.Sh AUTHORS 132.An -nosplit 133The original implementation was done by 134.An Poul-Henning Kamp Aq phk@FreeBSD.org 135with minor improvements from 136.An Ulrich Sp\(:orlein Aq uspoerlein@gmail.com . 137.Pp 138This manual page was written by 139.An Ulrich Sp\(:orlein . 140.Sh BUGS 141Reading from media where the sectorsize is not a power of 2 will make all 1421 MB reads fail. 143This is due to the DMA reads being split up into blocks of at most 128kB. 144These reads then fail if the sectorsize is not a divisor of 128kB. 145When reading a full raw audio CD, this leads to roughly 700 error messages 146flying by. 147This is harmless. 148