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Updated: Thursday, June 13, 2019
 
 

innochecksum (1)

Name

innochecksum - offline InnoDB file checksum utility

Synopsis

innochecksum [options] file_name

Description

INNOCHECKSUM(1)              MySQL Database System             INNOCHECKSUM(1)



NAME
       innochecksum - offline InnoDB file checksum utility

SYNOPSIS
       innochecksum [options] file_name

DESCRIPTION
       innochecksum prints checksums for InnoDB files. This tool reads an
       InnoDB tablespace file, calculates the checksum for each page, compares
       the calculated checksum to the stored checksum, and reports mismatches,
       which indicate damaged pages. It was originally developed to speed up
       verifying the integrity of tablespace files after power outages but can
       also be used after file copies. Because checksum mismatches cause
       InnoDB to deliberately shut down a running server, it may be preferable
       to use this tool rather than waiting for an in-production server to
       encounter the damaged pages.

       innochecksum cannot be used on tablespace files that the server already
       has open. For such files, you should use CHECK TABLE to check tables
       within the tablespace. Attempting to run innochecksum on a tablespace
       that the server already has open will result in an "Unable to lock
       file" error.

       If checksum mismatches are found, you would normally restore the
       tablespace from backup or start the server and attempt to use mysqldump
       to make a backup of the tables within the tablespace.

       Invoke innochecksum like this:

           shell> innochecksum [options] file_name

       innochecksum Options.PP innochecksum supports the following options.
       For options that refer to page numbers, the numbers are zero-based.

       o   --help, -?

           Displays command line help. Example usage:

               shell> innochecksum --help

       o   --info, -I

           Synonym for --help. Displays command line help. Example usage:

               shell> innochecksum --info

       o   --version, -V

           Displays version information. Example usage:

               shell> innochecksum --version

       o   --verbose, -v

           Verbose mode; prints a progress indicator to the log file every
           five seconds. In order for the progress indicator to be printed,
           the log file must be specified using the --log option. To turn on
           verbose mode, run:

               shell> innochecksum --verbose

           To turn off verbose mode, run:

               shell> innochecksum --verbose=FALSE

           The --verbose option and --log option can be specified at the same
           time. For example:

               shell> innochecksum --verbose --log=/var/lib/mysql/test/logtest.txt

           To locate the progress indicator information in the log file, you
           can perform the following search:

               shell> cat ./logtest.txt | grep -i "okay"

           The progress indicator information in the log file appears similar
           to the following:

               page 1663 okay: 2.863% done
               page 8447 okay: 14.537% done
               page 13695 okay: 23.568% done
               page 18815 okay: 32.379% done
               page 23039 okay: 39.648% done
               page 28351 okay: 48.789% done
               page 33023 okay: 56.828% done
               page 37951 okay: 65.308% done
               page 44095 okay: 75.881% done
               page 49407 okay: 85.022% done
               page 54463 okay: 93.722% done
               ...

       o   --count, -c

           Print a count of the number of pages in the file and exit. Example
           usage:

               shell> innochecksum --count ../data/test/tab1.ibd

       o   --start-page=num, -s num

           Start at this page number. Example usage:

               shell> innochecksum --start-page=600 ../data/test/tab1.ibd

           or:

               shell> innochecksum -s 600 ../data/test/tab1.ibd

       o   --end-page=num, -e num

           End at this page number. Example usage:

               shell> innochecksum --end-page=700 ../data/test/tab1.ibd

           or:

               shell> innochecksum --p 700 ../data/test/tab1.ibd

       o   --page=num, -p num

           Check only this page number. Example usage:

               shell> innochecksum --page=701 ../data/test/tab1.ibd

       o   --strict-check, -C

           Specify a strict checksum algorithm. Options include innodb, crc32,
           and none.

           In this example, the innodb checksum algorithm is specified:

               shell> innochecksum --strict-check=innodb ../data/test/tab1.ibd

           In this example, the crc32 checksum algorithm is specified:

               shell> innochecksum -C crc32 ../data/test/tab1.ibd

           The following conditions apply:

           o   If you do not specify the --strict-check option, innochecksum
               validates against innodb, crc32 and none.

           o   If you specify the none option, only checksums generated by
               none are allowed.

           o   If you specify the innodb option, only checksums generated by
               innodb are allowed.

           o   If you specify the crc32 option, only checksums generated by
               crc32 are allowed.

       o   --no-check, -n

           Ignore the checksum verification when rewriting a checksum. This
           option may only be used with the innochecksum --write option. If
           the --write option is not specified, innochecksum will terminate.

           In this example, an innodb checksum is rewritten to replace an
           invalid checksum:

               shell> innochecksum --no-check --write innodb ../data/test/tab1.ibd

       o   --allow-mismatches, -a

           The maximum number of checksum mismatches allowed before
           innochecksum terminates. The default setting is 0. If
           --allow-mismatches=N, where N>=0, N mismatches are permitted and
           innochecksum terminates at N+1. When --allow-mismatches is set to
           0, innochecksum terminates on the first checksum mismatch.

           In this example, an existing innodb checksum is rewritten to set
           --allow-mismatches to 1.

               shell> innochecksum --allow-mismatches=1 --write innodb ../data/test/tab1.ibd

           With --allow-mismatches set to 1, if there is a mismatch at page
           600 and another at page 700 on a file with 1000 pages, the checksum
           is updated for pages 0-599 and 601-699. Because --allow-mismatches
           is set to 1, the checksum tolerates the first mismatch and
           terminates on the second mismatch, leaving page 600 and pages
           700-999 unchanged.

       o   --write=name, -w num

           Rewrite a checksum. When rewriting an invalid checksum, the
           --no-check option must be used together with the --write option.
           The --no-check option tells innochecksum to ignore verification of
           the invalid checksum. You do not have to specify the --no-check
           option if the current checksum is valid.

           An algorithm must be specified when using the --write option.
           Possible values for the --write option are:

           o   innodb: A checksum calculated in software, using the original
               algorithm from InnoDB.

           o   crc32: A checksum calculated using the crc32 algorithm,
               possibly done with a hardware assist.

           o   none: A constant number.

           The --write option rewrites entire pages to disk. If the new
           checksum is identical to the existing checksum, the new checksum is
           not written to disk in order to minimize I/O.

           innochecksum obtains an exclusive lock when the --write option is
           used.

           In this example, a crc32 checksum is written for tab1.ibd:

               shell> innochecksum -w crc32 ../data/test/tab1.ibd

           In this example, a crc32 checksum is rewritten to replace an
           invalid crc32 checksum:

               shell> innochecksum --no-check --write crc32 ../data/test/tab1.ibd

       o   --page-type-summary, -S

           Display a count of each page type in a tablespace. Example usage:

               shell> innochecksum --page-type-summary ../data/test/tab1.ibd

           Sample output for --page-type-summary:

               File::../data/test/tab1.ibd
               ================PAGE TYPE SUMMARY==============
               #PAGE_COUNT PAGE_TYPE
               ===============================================
                      2        Index page
                      0        Undo log page
                      1        Inode page
                      0        Insert buffer free list page
                      2        Freshly allocated page
                      1        Insert buffer bitmap
                      0        System page
                      0        Transaction system page
                      1        File Space Header
                      0        Extent descriptor page
                      0        BLOB page
                      0        Compressed BLOB page
                      0        Other type of page
               ===============================================
               Additional information:
               Undo page type: 0 insert, 0 update, 0 other
               Undo page state: 0 active, 0 cached, 0 to_free, 0 to_purge, 0 prepared, 0 other

       o   --page-type-dump, -D

           Dump the page type information for each page in a tablespace to
           stderr or stdout. Example usage:

               shell> innochecksum --page-type-dump=/tmp/a.txt ../data/test/tab1.ibd

       o   --log, -l

           Log output for the innochecksum tool. A log file name must be
           provided. Log output contains checksum values for each tablespace
           page. For uncompressed tables, LSN values are also provided. The
           --log replaces the --debug option, which was available in earlier
           releases. Example usage:

               shell> innochecksum --log=/tmp/log.txt ../data/test/tab1.ibd

           or:

               shell> innochecksum -l /tmp/log.txt ../data/test/tab1.ibd

       o   - option.

           Specify the - option to read from standard input. If the - option
           is missing when "read from standard in" is expected, innochecksum
           will output innochecksum usage information indicating that the "-"
           option was omitted. Example usages:

               shell> cat t1.ibd | innochecksum -

           In this example, innochecksum writes the crc32 checksum algorithm
           to a.ibd without changing the original t1.ibd file.

               shell> cat t1.ibd | innochecksum --write=crc32 - > a.ibd
       Running innochecksum on Multiple User-defined Tablespace Files.PP The
       following examples demonstrate how to run innochecksum on multiple
       user-defined tablespace files (.ibd files).

       Run innochecksum for all tablespace (.ibd) files in the "test"
       database:

           shell> innochecksum ./data/test/*.ibd

       Run innochecksum for all tablespace files (.ibd files) that have a file
       name starting with "t":

           shell> innochecksum ./data/test/t*.ibd

       Run innochecksum for all tablespace files (.ibd files) in the data
       directory:

           shell> innochecksum ./data/*/*.ibd


           Note
           Running innochecksum on multiple user-defined tablespace files is
           not supported on Windows operating systems, as Windows shells such
           as cmd.exe do not support glob pattern expansion. On Windows
           systems, innochecksum must be run separately for each user-defined
           tablespace file. For example:

               cmd> innochecksum.exe t1.ibd
               cmd> innochecksum.exe t2.ibd
               cmd> innochecksum.exe t3.ibd
       Running innochecksum on Multiple System Tablespace Files.PP By default,
       there is only one InnoDB system tablespace file (ibdata1) but multiple
       files for the system tablespace can be defined using the
       innodb_data_file_path option. In the following example, three files for
       the system tablespace are defined using the innodb_data_file_path
       option: ibdata1, ibdata2, and ibdata3.

           shell> ./bin/mysqld --no-defaults --innodb-data-file-path="ibdata1:10M;ibdata2:10M;ibdata3:10M:autoextend"

       The three files (ibdata1, ibdata2, and ibdata3) form one logical system
       tablespace. To run innochecksum on multiple files that form one logical
       system tablespace, innochecksum requires the - option to read
       tablespace files in from standard input, which is equivalent to
       concatenating multiple files to create one single file. For the example
       provided above, the following innochecksum command would be used:

           shell> cat ibdata* | innochecksum -

       Refer to the innochecksum options information for more information
       about the "-" option.

           Note
           Running innochecksum on multiple files in the same tablespace is
           not supported on Windows operating systems, as Windows shells such
           as cmd.exe do not support glob pattern expansion. On Windows
           systems, innochecksum must be run separately for each system
           tablespace file. For example:

               cmd> innochecksum.exe ibdata1
               cmd> innochecksum.exe ibdata2
               cmd> innochecksum.exe ibdata3

COPYRIGHT
       Copyright (C) 1997, 2018, Oracle and/or its affiliates. All rights
       reserved.

       This documentation is free software; you can redistribute it and/or
       modify it only under the terms of the GNU General Public License as
       published by the Free Software Foundation; version 2 of the License.

       This documentation is distributed in the hope that it will be useful,
       but WITHOUT ANY WARRANTY; without even the implied warranty of
       MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
       General Public License for more details.

       You should have received a copy of the GNU General Public License along
       with the program; if not, write to the Free Software Foundation, Inc.,
       51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA or see
       http://www.gnu.org/licenses/.



ATTRIBUTES
       See attributes(7) for descriptions of the following attributes:


       +---------------+-------------------+
       |ATTRIBUTE TYPE | ATTRIBUTE VALUE   |
       +---------------+-------------------+
       |Availability   | database/mysql-57 |
       +---------------+-------------------+
       |Stability      | Uncommitted       |
       +---------------+-------------------+
SEE ALSO
       For more information, please refer to the MySQL Reference Manual, which
       may already be installed locally and which is also available online at
       http://dev.mysql.com/doc/.

AUTHOR
       Oracle Corporation (http://dev.mysql.com/).



NOTES
       This software was built from source available at
       https://github.com/oracle/solaris-userland.  The original community
       source was downloaded from
       https://dev.mysql.com/get/Downloads/MySQL-5.7/mysql-boost-5.7.25.tar.gz

       Further information about this software can be found on the open source
       community website at https://dev.mysql.com/.



MySQL 5.7                         12/20/2018                   INNOCHECKSUM(1)