I find that most of my clients are not documenting their databases at all and I find that pretty scary. To introduce some better practice, I would like to know what tools/process people are using. ...
The docs for 5.1 say that I can set log_warnings = 2 to capture Aborted_connects in the error log. This bug report suggests that this was only merged into 5.5 and 6.0 (and maybe 5.2) but not into 5.1....