MySQL 5.7 Reference Manual Including MySQL NDB Cluster 7.5 and NDB Cluster 7.6
As of MySQL 5.7.17, MySQL Server includes a plugin library that enables administrators to introduce an increasing delay in server response to connection attempts after a configurable number of consecutive failed attempts. This capability provides a deterrent that slows down brute force attacks against MySQL user accounts. The plugin library contains two plugins:
CONNECTION_CONTROL
checks incoming
connection attempts and adds a delay to server responses as
necessary. This plugin also exposes system variables that
enable its operation to be configured and a status variable
that provides rudimentary monitoring information.
The CONNECTION_CONTROL
plugin uses the
audit plugin interface (see
Writing Audit Plugins). To collect
information, it subscribes to the
MYSQL_AUDIT_CONNECTION_CLASSMASK
event
class, and processes
MYSQL_AUDIT_CONNECTION_CONNECT
and
MYSQL_AUDIT_CONNECTION_CHANGE_USER
subevents to check whether the server should introduce a delay
before responding to connection attempts.
CONNECTION_CONTROL_FAILED_LOGIN_ATTEMPTS
implements an INFORMATION_SCHEMA
table that
exposes more detailed monitoring information for failed
connection attempts.
The following sections provide information about
connection-control plugin installation and configuration. For
information about the
CONNECTION_CONTROL_FAILED_LOGIN_ATTEMPTS
table, see
Section 23.34.1, “The INFORMATION_SCHEMA CONNECTION_CONTROL_FAILED_LOGIN_ATTEMPTS Table”.