MySQL 5.6 Reference Manual Including MySQL NDB Cluster 7.3-7.4 Reference Guide
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. As of MySQL 5.6.16, innochecksum
supports files greater than 2GB in size. Previously,
innochecksum only supported files up to 2GB
in size.
innochecksum does not support tablespaces that contain compressed 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 mysqldump 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.