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 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., 2010-2025 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 Documentation, available online at https://mariadb.com/docs/

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