Mysql checksum for master-slave replication returning different values, despite being identical I've set up a master slave replication in mysql and to make sure that I know if the data starts getting out of sync I created a script that:


Locks both databases on both servers.
Prints the checksums of all the tables to a text file.
Copy's the slave checksum text file to master.
Compares the both files to see if anything is different.


But on some tables I got different checksums. So I downloaded both those tables and created another script to find whats different on them. And Nothing is different! They're identical.

I only get the different checksums on tables that have float variables, so I suspect it has something to do with that.

I do have slightly different versions of mysql installed, could this be causing it?

+-------------------------+-----------------------------+
| Variable_name           | Value                       |
+-------------------------+-----------------------------+
| innodb_version          | 5.5.34                      |
| protocol_version        | 10                          |
| slave_type_conversions  |                             |
| version                 | 5.5.34-0ubuntu0.13.04.1-log |
| version_comment         | (Ubuntu)                    |
| version_compile_machine | x86_64                      |
| version_compile_os      | debian-linux-gnu            |
+-------------------------+-----------------------------+

+-------------------------+-----------------------------+
| Variable_name           | Value                       |
+-------------------------+-----------------------------+
| innodb_version          | 5.5.37                      |
| protocol_version        | 10                          |
| slave_type_conversions  |                             |
| version                 | 5.5.37-0ubuntu0.14.04.1-log |
| version_comment         | (Ubuntu)                    |
| version_compile_machine | x86_64                      |
| version_compile_os      | debian-linux-gnu            |
+-------------------------+-----------------------------+


Anyone of you know what could be causing this?
There is better way to check whether the master and it's slaves are in sync.  

Run pt-table-checksum on the master. 

Then if it shows some tables are different use this script to see where exactly the difference is. http://bazaar.launchpad.net/~akuzminsky/+junk/stats-scripts/view/head:/compare_tables.sh

./compare_tables.sh master_ip slave_ip database table