NAME

badblocks - 查詢?cè)O(shè)備的壞區(qū)塊  

語(yǔ)法（SYNPSIS）

badblocks [ -svwnf ] [ -b block-size ] [ -c blocks_at_once ] [ -i input_file ] [ -o output_file ] [ -p num_passes ] device [ blocks-count ] [ start-block ]  

（描述）DESCRIPTION

badblocks 被用來(lái)在設(shè)備（通常是磁盤分區(qū)）中檢測(cè)壞區(qū)塊。 device 參數(shù)是設(shè)備的名字(例如 /dev/hdc1). blocks-count 參數(shù)是設(shè)備上總的區(qū)塊數(shù)目；如果沒(méi)有指定這個(gè)參數(shù)，默認(rèn)值就是設(shè)備的容量大小。 start-block參數(shù)是一個(gè)可選參數(shù)，它指定從多少區(qū)塊號(hào)開始進(jìn)行檢測(cè)。因此，檢測(cè)允許從磁盤的中間部分開始。  

選項(xiàng)（OPTIONS）

-b block-size

以字節(jié)為單位，指定區(qū)塊的大小。

-c number of blocks

每一次檢測(cè)區(qū)塊的數(shù)目。默認(rèn)值是16。增加這個(gè)數(shù)目可以增加檢測(cè) 壞塊 的效率可同時(shí)也會(huì)增加內(nèi)存的耗費(fèi)。 Badblocks 命令在只讀模式下需要花費(fèi)與每一次檢測(cè)的區(qū)塊相同數(shù)目的內(nèi)存容量。在讀寫模式下，這個(gè)比例是兩倍而在非破壞性的讀寫模式下，這個(gè)比例是三倍。如果你將參數(shù)“num-of-blocks”設(shè)置太大的話， badblocks 將會(huì)在分派緩存時(shí)會(huì)因?yàn)橐粋€(gè)內(nèi)存溢出錯(cuò)誤而立即退出。當(dāng)然如果你在非破壞性的讀寫模式下將該值設(shè)置得過(guò)低，那么在一個(gè)不穩(wěn)定的磁盤上的有問(wèn)題的區(qū)塊也許會(huì)因?yàn)榇疟P的磁道緩沖的作用而不被檢測(cè)出來(lái)。

-f

正常情況下，badblocks命令不會(huì)在一個(gè)已經(jīng)激活的設(shè)備上讀寫模式或者是非破壞性的讀寫模式的檢測(cè)，因?yàn)檫@可能會(huì)導(dǎo)致系統(tǒng)的崩潰。使用 -f 標(biāo)志可以使這種情況強(qiáng)制執(zhí)行，但是最好不要在正常的情況下使用它。如果/etc/mtab文件發(fā)生了錯(cuò)誤，而設(shè)備實(shí)際上并沒(méi)有被激活的時(shí)候，這個(gè)參數(shù)才會(huì)是安全的。

-i input_file

讀入一個(gè)已知的壞塊列表。 Badblocks 命令將會(huì)跳過(guò)對(duì)這些已知是壞塊的區(qū)塊檢查。如果 input_file 參數(shù)是“-”，則列表從標(biāo)準(zhǔn)輸入讀入。在這個(gè)列表中列舉出的區(qū)塊也會(huì)在 新的 壞道記錄文件或者壞道記錄輸出時(shí)被忽略掉。 dumpe2fs(8) 的 -b 選項(xiàng)能夠在一個(gè)已有的文件系統(tǒng)中得到被標(biāo)記為壞塊的列表，而且已經(jīng)做成了符合這個(gè)選項(xiàng)的格式。

-o output_file

將壞塊的列表寫到指定的文件中。如果沒(méi)有這個(gè)選項(xiàng)， badblocks 命令會(huì)在標(biāo)準(zhǔn)輸出中輸出這個(gè)列表。其格式是與 e2fsck(8) 或者 mke2fs(8). 的 -l 選項(xiàng)的要求相適應(yīng)的。

-p num_passes

重復(fù)的掃描磁盤，直到重復(fù)“num_passes”遍磁盤掃描后也沒(méi)有發(fā)現(xiàn)新的區(qū)塊后結(jié)束。默認(rèn)值是0。表示 badblocks 命令成功執(zhí)行一遍掃描后就會(huì)結(jié)束。

-n

使用非破壞性的讀寫模式。默認(rèn)值是非破壞性的只讀模式測(cè)試。這個(gè)選項(xiàng)不能與 -w 選項(xiàng)一起使用，因?yàn)樗鼈兪腔コ獾摹?

-s

通過(guò)輸出正在被檢測(cè)的區(qū)塊的號(hào)碼以表示檢測(cè)進(jìn)程。

-v

混雜模式檢測(cè)。

-w

使用寫模式測(cè)試。通過(guò)使用這個(gè)選項(xiàng) badblocks 通過(guò)往每個(gè)區(qū)塊上寫入一些特定的字符（0xaa，0x55，0xff，0x00），讀出來(lái)后再比較其內(nèi)容，決定是否為壞塊。這個(gè)選項(xiàng)不能與 -n 選項(xiàng)一起使用，因?yàn)樗鼈兪腔コ獾摹?

警告（WARNING）

千萬(wàn)不要將 -w 選項(xiàng)用在一個(gè)已經(jīng)包含了文件系統(tǒng)的設(shè)備上。這個(gè)選項(xiàng)會(huì)刪除掉原有的數(shù)據(jù)！如果你想要在已經(jīng)有文件系統(tǒng)的設(shè)備上執(zhí)行讀寫模式檢測(cè)，請(qǐng)使用 -n 選項(xiàng)。雖然慢點(diǎn)，可是它能夠保護(hù)你的數(shù)據(jù)不受傷害。  

作者（AUTHOR）

badblocks 作者是Remy Card <Remy.Card@linux.org>. 維護(hù)人 Theodore Ts'o <tytso@alum.mit.edu>. 非破壞性的讀寫模式測(cè)試由David Beattie <dbeattie@softhome.net>進(jìn)行.  

有效資源（AVAILABILITY）

badblocks 是e2fsprogs套件的一部分。能夠從支持匿名訪問(wèn)的ftp站點(diǎn)tsx-11.mit.edu的/pub/linux/packages/ext2fs目錄下取得。  

另外請(qǐng)參考

e2fsck(8), mke2fs(8)

#p#

NAME

badblocks - search a device for bad blocks  

SYNOPSIS

badblocks [ -svwnf ] [ -b block-size ] [ -c blocks_at_once ] [ -i input_file ] [ -o output_file ] [ -p num_passes ] [ -t test_pattern ] device [ last-block ] [ start-block ]  

DESCRIPTION

badblocks is used to search for bad blocks on a device (usually a disk partition). device is the special file corresponding to the device (e.g /dev/hdc1). 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. start-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.

Important note: If the output of badblocks is going to be fed to the e2fsck or 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. For this reason, it is strongly recommended that users not run badblocks directly, but rather use the -c option of the e2fsck and mke2fs programs.  

OPTIONS

-b block-size

Specify the size of blocks in bytes.

-c number of blocks

is the number of blocks which are tested at a time. The default is 64.

-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 filesystem even if it is mounted read-only. This can be overriden using the -f flag, but should almost never be used --- if you think you're smarter than the 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.

-i input_file

Read a list of already existing known bad blocks. Badblocks will skip testing these blocks since they are known to be bad. If 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 new bad blocks produced on the standard output or in the output file. The -b option of dumpe2fs(8) can be used to retrieve the list of blocks currently marked bad on an existing filesystem, in a format suitable for use with this option.

-o output_file

Write the list of bad blocks to the specified file. Without this option, badblocks displays the list on its standard output. The format of this file is suitable for use by the -l option in e2fsck(8) or mke2fs(8).

-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 badblocks will exit after the first pass.

-t test_pattern

Specify a test pattern to be read (and written) to disk blocks. The 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 (-w) and non-destructive (-n) modes, one or more test patterns may be specified by specifiying the -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 an one pattern before proceeding to the next pattern.

-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 -w option, as they are mutually exclusive.

-s

Show the progress of the scan by writing out the block numbers as they are checked.

-v

Verbose mode.

-w

Use write-mode test. With this option, 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 -n option, as they are mutually exclusive.

WARNING

Never use the -w option on an 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 -n option instead. It is slower, but it will preserve your data.  

AUTHOR

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>.  

AVAILABILITY

badblocks is part of the e2fsprogs package and is available from http://e2fsprogs.sourceforge.net.  

SEE ALSO

e2fsck(8), mke2fs(8)