Generally, changing your MySQL client application is the easiest and recommended method. For example, given a typical structure like the one in the following figure, you would modify the client application so that it communicated to the proxy rather than directly with the MySQL server,
The following figure shows an example of the structure when communicating through the proxy:
To enable Query Analyzer within your MySQL client application:
Make sure that the MySQL Enterprise Service Manager and your MySQL Enterprise Agent are configured and running.
-
Confirm the configuration of your agent by examining the contents of the
etc/mysql-monitor-agent.inifile within your installed Agent directory.Queries are sent to the host specified in the
proxy-backend-addressesparameter, and the agent listens for connections to be redirected to the server on the host name and port configured in theproxy-addressparameter. -
Now modify your MySQL client application to communicate with the address specified in the
proxy-addressparameter.Alternatively, if you do not want to modify your application directly, you can use iptables or firewall rules to redirect queries from the original host/port combination to the agent's port.
Because connections to the MySQL server come from the proxy, not the original host, the user credentials must be have a suitable
GRANTstatement for connections fromlocalhost, or the host on which the agent and its proxy component run. The user name and password information are passed directly through the proxy from the client to the server. Confirm that your MySQL client application still operates normally. There should be no difference between communicating directly with the MySQL server and communicating via the proxy.
If you are using the mysql client to connect
to the proxy and your backend servers, make sure that you are
communicating with the proxy over the right port. By default, if
you specify localhost as the host name, then
mysql connects using the local Unix domain
socket, rather than the TCP/IP socket.
You can enforce mysql to use the right port
either by explicitly requesting the protocol type, or by using
the IP address rather than localhost. For
example, both of these command lines start the client using the
right protocol:
shell> mysql --port=6446 --protocol=tcp shell> mysql --port=6446 --host=127.0.0.1
It is recommended that you use one agent and associated proxy per MySQL server instance. A single proxy is not able to forward queries to multiple MySQL server backends.
