If the following error occurs, it means that mysqld has received many connection requests from the given host that were interrupted in the middle:
Host 'host_name' is blocked because of many connection errors. Unblock with 'mysqladmin flush-hosts'
The value of the
variable determines how many successive interrupted connection
requests are permitted. After
requests without a successful connection,
mysqld assumes that something is wrong (for
example, that someone is trying to break in), and blocks the
host from further connections until you flush the host cache
by executing a
statement that truncates the Performance Schema
host_cache table, or a
mysqladmin flush-hosts command.
To adjust the permitted number of successive connection
max_connect_errors at server
startup. For example, put these lines in the server
The value can also be set at runtime:
SET GLOBAL max_connect_errors=10000;
If you get the
error message for a given host, you should first verify that
there is nothing wrong with TCP/IP connections from that host.
If you are having network problems, it does no good to
increase the value of
host_name' is blocked
For more information about how the host cache works, see Section 18.104.22.168, “DNS Lookup Optimization and the Host Cache”.