I was fixing MySQL replication on a slave this past week. Everything seemed to be ready to go after bringing data over from the master manually. I went to connect the slave to the master and nothing happened. Whaaaaaa?

Last_IO_Errno: 1045
Last_IO_Error: error connecting to master 'repl@blah.local:3306' - retry-time: 60 retries: 86400

Let me look up MySQL error code 1045:

    Message: Access denied for user '%s'@'%s' (using password: %s)

That’s not helpful. After some additional testing I realized the password might be too long. Sure enough, the CHANGE MASTER TO syntax guide states MASTER_PASSWORD has a maximum length of 32 characters (despite the MySQL client having a longer limit).

It’s annoying that this limit exists and the error 1045 message isn’t clearer about it. Hopefully you found this very early on in your search for an answer.