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diff --git a/misc/badblocks.8.in b/misc/badblocks.8.in new file mode 100644 index 0000000..6c96cdc --- /dev/null +++ b/misc/badblocks.8.in @@ -0,0 +1,234 @@ +.\" -*- nroff -*- +.TH BADBLOCKS 8 "@E2FSPROGS_MONTH@ @E2FSPROGS_YEAR@" "E2fsprogs version @E2FSPROGS_VERSION@" +.SH NAME +badblocks \- search a device for bad blocks +.SH SYNOPSIS +.B badblocks +[ +.B \-svwnfBX +] +[ +.B \-b +.I block_size +] +[ +.B \-c +.I blocks_at_once +] +[ +.B \-d +.I read_delay_factor +] +[ +.B \-e +.I max_bad_blocks +] +[ +.B \-i +.I input_file +] +[ +.B \-o +.I output_file +] +[ +.B \-p +.I num_passes +] +[ +.B \-t +.I test_pattern +] +.I device +[ +.I last_block +] [ +.I first_block +] +.SH DESCRIPTION +.B badblocks +is used to search for bad blocks on a device (usually a disk partition). +.I device +is the special file corresponding to the device (e.g +.IR /dev/hdc1 ). +.I last_block +is the last block to be checked; if it is not specified, the last block +on the device is used as a default. +.I first_block +is an optional parameter specifying the starting block number +for the test, which allows the testing to start in the middle of the +disk. If it is not specified the first block on the disk is used as a default. +.PP +.B Important note: +If the output of +.B badblocks +is going to be fed to the +.B e2fsck +or +.B mke2fs +programs, it is important that the block size is properly specified, +since the block numbers which are generated are very dependent on the +block size in use by the file system. +For this reason, it is strongly recommended that +users +.B not +run +.B badblocks +directly, but rather use the +.B \-c +option of the +.B e2fsck +and +.B mke2fs +programs. +.SH OPTIONS +.TP +.BI \-b " block_size" +Specify the size of blocks in bytes. The default is 1024. +.TP +.BI \-c " number of blocks" +is the number of blocks which are tested at a time. The default is 64. +.TP +.BI \-d " read delay factor" +This parameter, if passed and non-zero, will cause bad blocks to sleep +between reads if there were no errors encountered in the read +operation; the delay will be calculated as a percentage of the time it +took for the read operation to be performed. In other words, a value of +100 will cause each read to be delayed by the amount the previous read +took, and a value of 200 by twice the amount. +.TP +.BI \-e " max bad block count" +Specify a maximum number of bad blocks before aborting the test. The +default is 0, meaning the test will continue until the end of the test +range is reached. +.TP +.B \-f +Normally, badblocks will refuse to do a read/write or a non-destructive +test on a device which is mounted, since either can cause the system to +potentially crash and/or damage the file system even if it is mounted +read-only. This can be overridden using the +.B \-f +flag, but should almost never be used --- if you think you're smarter +than the +.B badblocks +program, you almost certainly aren't. The only time when this option +might be safe to use is if the /etc/mtab file is incorrect, and the device +really isn't mounted. +.TP +.BI \-i " input_file" +Read a list of already existing known bad blocks. +.B Badblocks +will skip testing these blocks since they are known to be bad. If +.I input_file +is specified as "-", the list will be read from the standard input. +Blocks listed in this list will be omitted from the list of +.I new +bad blocks produced on the standard output or in the output file. +The +.B \-b +option of +.BR dumpe2fs (8) +can be used to retrieve the list of blocks currently marked bad on +an existing file system, in a format suitable for use with this option. +.TP +.B \-n +Use non-destructive read-write mode. By default only a non-destructive +read-only test is done. This option must not be combined with the +.B \-w +option, as they are mutually exclusive. +.TP +.BI \-o " output_file" +Write the list of bad blocks to the specified file. Without this option, +.B badblocks +displays the list on its standard output. The format of this file is suitable +for use by the +. +.B \-l +option in +.BR e2fsck (8) +or +.BR mke2fs (8). +.TP +.BI \-p " num_passes" +Repeat scanning the disk until there are no new blocks discovered in +num_passes consecutive scans of the disk. +Default is 0, meaning +.B badblocks +will exit after the first pass. +.TP +.B \-s +Show the progress of the scan by writing out rough percentage completion +of the current badblocks pass over the disk. Note that badblocks may do +multiple test passes over the disk, in particular if the +.B \-p +or +.B \-w +option is requested by the user. +.TP +.BI \-t " test_pattern" +Specify a test pattern to be read (and written) to disk blocks. The +.I test_pattern +may either be a numeric value between 0 and ULONG_MAX-1 inclusive, or the word +"random", which specifies that the block should be filled with a random +bit pattern. +For read/write (\fB-w\fR) and non-destructive (\fB-n\fR) modes, +one or more test patterns may be specified by specifying the +.B -t +option for each test pattern desired. For +read-only mode only a single pattern may be specified and it may not be +"random". Read-only testing with a pattern assumes that the +specified pattern has previously been written to the disk - if not, large +numbers of blocks will fail verification. +If multiple patterns +are specified then all blocks will be tested with one pattern +before proceeding to the next pattern. +.TP +.B \-v +Verbose mode. Will write the number of read errors, write errors and data- +corruptions to stderr. +.TP +.B \-w +Use write-mode test. With this option, +.B badblocks +scans for bad blocks by writing some patterns (0xaa, 0x55, 0xff, 0x00) on +every block of the device, reading every block and comparing the contents. +This option may not be combined with the +.B \-n +option, as they are mutually exclusive. +.TP +.B \-B +Use buffered I/O and do not use Direct I/O, even if it is available. +.TP +.B \-X +Internal flag only to be used by +.BR e2fsck (8) +and +.BR mke2fs (8). +It bypasses the exclusive mode in-use device safety check. +.SH WARNING +Never use the +.B \-w +option on a device containing an existing file system. +This option erases data! If you want to do write-mode testing on +an existing file system, use the +.B \-n +option instead. It is slower, but it will preserve your data. +.PP +The +.B \-e +option will cause badblocks to output a possibly incomplete list of +bad blocks. Therefore it is recommended to use it only when one wants +to know if there are any bad blocks at all on the device, and not when +the list of bad blocks is wanted. +.SH AUTHOR +.B badblocks +was written by Remy Card <Remy.Card@linux.org>. Current maintainer is +Theodore Ts'o <tytso@alum.mit.edu>. Non-destructive read/write test +implemented by David Beattie <dbeattie@softhome.net>. +.SH AVAILABILITY +.B badblocks +is part of the e2fsprogs package and is available from +http://e2fsprogs.sourceforge.net. +.SH SEE ALSO +.BR e2fsck (8), +.BR mke2fs (8) |