innochecksum
Contents
innochecksum is a tool for printing checksums for InnoDB files.
Usage
innochecksum [options] file_name
Description
It 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 innochecksum 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 mysqldump to make a backup of the tables within the tablespace.
Options
innochecksum supports the following options. For options that refer to page numbers, the numbers are zero-based.
| Option | Description |
|---|---|
| -c | Print a count of the number of pages in the file. |
| -d | Debug mode; prints checksums for each page. |
| -e num | End at this page number. |
| -p num | Check only this page number. |
| -s num | Start at this page number. |
| -v | Verbose mode; print a progress indicator every five seconds. |
