MySQL flush-hosts and ERROR 1129 (HY000)

Often we see an error such as:

ERROR 1129 (HY000): Host 'nn.nn.nn.nn' is blocked because of many connection errors; unblock with 'mysqladmin flush-hosts'

 

Any issue I've come across is where the database instance is bound to the ip address that is blocked and while there may be other ways around this, Ive had to resort to running the below command from another host;

mysqladmin --host=nn.nn.nn.nn -port=3306 -u username -p flush-hosts

where the ip address is of course the host.

It should be noted that there were no errors in the mysql log relating to the above.