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 will cause InnoDB to
       deliberately shut down a running server, it can be preferable to use this tool rather than
       waiting for a server in production usage 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.

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

       Invoke innochecksum like this:

           shell> innochecksum [options] file_name

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

       •   -?, --help

           Displays help and exits.

       •   -a num, --allow-mismatches=#

           Maximum checksum mismatch allowed before innochecksum terminates. Defaults to 0, which
           terminates on the first mismatch.

       •   -c, --count

           Print a count of the number of pages in the file.

       •   -e num, --end-page=#

           End at this page number.

       •   -i, --per-page-details

           Print out per-page detail information.

       •   -I, --info

           Synonym for --help.

       •   -f, --leaf

           Examine leaf index pages.

       •   -l fn, --log=fn

           Log output to the specified filename, fn.

       •   -m num, --merge=#

           Leaf page count if merge given number of consecutive pages.

       •   -n, --no-check

           Ignore the checksum verification. Until MariaDB 10.6, must be used with the --write
           option.

       •   -p num, --page-num=#

           Check only this page number.

       •   -D name, --page-type-dump=name

           Dump the page type info for each page in a tablespace.

       •   -S, --page-type-summary

           Display a count of each page type in a tablespace.

       •   -s num, --start-page

           Start at this page number.

       •   -u, --skip-corrupt

           Skip corrupt pages.

       •   -C name, --strict-check=name

           Specify the strict checksum algorithm. One of: crc32, innodb, none. If not specified,
           validates against innodb, crc32 and none. Removed in MariaDB 10.6.

       •   -w name, --write=name

           Rewrite the checksum algorithm. One of crc32, innodb, none. An exclusive lock is
           obtained during use. Use in conjunction with the -no-check option to rewrite an
           invalid checksum. Removed in MariaDB 10.6.

       •   -v, --verbose

           Verbose mode; print a progress indicator every five seconds.

       •   -V, --version

           Displays version information and exits.

COPYRIGHT

       Copyright 2007-2008 MySQL AB, 2008-2010 Sun Microsystems, Inc., 2010-2023 MariaDB
       Foundation

       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 02110-1335 USA or see http://www.gnu.org/licenses/.

SEE ALSO

       For more information, please refer to the MariaDB Knowledge Base, available online at
       https://mariadb.com/kb/

AUTHOR

       MariaDB Foundation (http://www.mariadb.org/).