ADC

Configure content switching for DataStream

You can segment traffic according to information in the SQL query, based on database names, user names, character sets, and packet size.

You can configure content switching policies with default syntax expressions to switch content based on connection properties. For example, user name and database name, command parameters, and the SQL query to select the server.

The default syntax expressions evaluate traffic associated with MYSQL and MS SQL database servers. Use request-based expressions in default syntax policies to make request switching decisions at the content switching virtual server bind point. Use response-based expressions (expressions that begin with MYSQL.RES) to evaluate server responses to user-configured health monitors.

For information about default syntax expressions, see Default Syntax Expressions: DataStream.

Note:

For databases, the load balancing can only occur on homogenous database servers (database servers that contain the exact same databases). For a configuration that contains unique databases on different servers, you must use content switching. If some of your database servers host identical content, you can use load balancing on those servers only. You can then use content switching policies to send requests to the load balancing virtual server that manages load balancing for those databases.

The Citrix ADC appliance currently stores the database name and login information during the database session. When a query is made to the database, it uses that information to connect to the specific database server.

Parameter values specific to DataStream

  • Protocol

    Use the MYSQL protocol type for MySQL databases and MSSQL protocol type for MS SQL databases while configuring virtual servers and services. The MySQL and TDS protocols are used by the clients to communicate with the respective database servers by using SQL queries. For information about the MySQL protocol, see http://dev.mysql.com/doc/internals/en/client-server-protocol.html. For information about the TDS protocol, see http://msdn.microsoft.com/en-us/library/dd304523(v=prot.13).aspx.

  • Port

    Port on which the virtual server listens for client connections. Use port 3306 for MySQL database servers.

  • MS SQL Server Version

    If you use Microsoft SQL Server, and expect some clients running a different version from your Microsoft SQL Server product, set the Server Version parameter for the content switching virtual server. The version setting provides compatibility between the client-side and server-side connections by ensuring that all communication conforms to the server’s version. For more information about setting the Server Version parameter, see Configuring the Microsoft SQL Server Version Setting.

Configure content switching for DataStream