I recently got an inquiry on how to receive an email every time a query was executed via the MySQL proxy. This is very simple and you can achieve it by simply piping the query to the *nix mail command. Here is the sample code (in a file caled send_mail.lua):

function read_query(packet)
  if string.byte(packet) == proxy.COM_QUERY then
    print("Hello world! Seen the query: " .. string.sub(packet, 2))
    print("Sending query to email:")
    os.execute("echo " .. string.sub(packet, 2) .. "| mail -s'Lua test' your.email.here@example.com ")
  end
end

To execute this, install proxy as per the instructions in the manual. Then simply run the proxy and point it at your script:

shell> bin/mysql-proxy --proxy-lua-script=send_email.lua &

Finally, connect to the proxy and issue a query:

…

In the last post, we saw how to create a test OpenLDAP server, populate it and secure it with SSL certificates. Now we are going to have a look at how to configure MySQL Enterprise Manager (MEM) to authenticate against LDAP. We will be examining a few different kinds of setup methods.

1. Using LDAP to fetch just the user password

The simplest form is to configure a user with MEM and set it to the LDAP type. The user’s role is setup in MEM during user creation time and is not fetched from LDAP. Below you can see the user definition page:

How to create a LDAP user in MEM - password only

The username is user1 as specified in MEM, but where do we get the password …

The latest 2.2 release of MySQL Enterprise Monitor (MEM) has the ability to authenticate against LDAP. I decided to test this setup and for that, I had to create and populate an OpenLDAP server, including STARTTLS/SSL certificates. This guide was done on CentOS 5.5 but it shouldn’t be much different in other Linux/Unix distributions. First, start off by installing the packages with:

root@shell> yum install openldap openldap-clients openldap-servers

Then head to /etc/openldap where you can set you domain and the DN for the LDAP manager user. I’ve inserted some useful comments into the slapd.conf file. Lines without comments have not been changed from the default slapd.conf file.

shell> grep -v "^#" /etc/openldap/slapd.conf | grep -v "^$"
include         /etc/openldap/schema/core.schema
include         /etc/openldap/schema/cosine.schema
include         /etc/openldap/schema/inetorgperson.schema
include …

With the release of MySQL Enterprise Monitor (MEM) 2.2, there is now the ability to monitor queries using the Query Analyzer (QUAN) without needing the agent proxy to be running. You can use a .NET or JDBC connector plugin to directly gather the query statistics. In the example below, we will use the MySQL Enterprise Plugin for Connector/J.

First, make sure both the Connector/J, the Connector/J plugin and the Apache Commons Logging jars are in the $CLASSPATH. At the time of writing, these are the files needed:

mysql-connector-java-5.1.12-bin.jar
c-java-mysql-enterprise-plugin-1.0.0.42.jar
required/commons-logging-1.1.1.jar

Then, add the plugin to the connection string so that it changes from something like this:

conn = …