MySQL error connections

连接MySQL得到这样的错误提示
Warning: mysql_pconnect(): Host '67.19.xx.xxx' is blocked because of many connection errors. Unblock with 'mysqladmin flush-hosts' in C:\Websites\ratedesi\include\connectdb.php on line 9 Host '67.19.xx.xxx' is blocked because of many connection errors. Unblock with 'mysqladmin flush-hosts'
在MySQL手册中找到这样的说明

A.2.5 `Host 'HOST_NAME' is blocked'
------------------------------------
If you get the following error, it means that `mysqld' has received
many connect requests from the host `'HOST_NAME that have
been interrupted in the middle:

Host 'HOST_NAME' is blocked because of many connection errors.
Unblock with 'mysqladmin flush-hosts'

The number of interrupted connect requests allowed is determined by
the value of the `max_connect_errors' system variable. After
`max_connect_errors' failed requests, `mysqld' assumes that
something is wrong (for example, that someone is trying to break
in), and blocks the host from further connections until you execute
a `mysqladmin flush-hosts' command or issue a `FLUSH HOSTS'
statement. See *Note server-system-variables::.

By default, `mysqld' blocks a host after 10 connection errors. You
can adjust the value by starting the server like this:

shell> mysqld_safe --max_connect_errors=10000 &
If you get this error message for a given host, you should first
verify that there isn't anything wrong with TCP/IP connections from
that host. If you are having network problems, it does you no good
to increase the value of the `max_connect_errors' variable.

这可能是比如PHP的未注销连接引起，查看MySQL的进程可以查看一下
mysqladmin -u -p processlist