6.4. Using Bridge Mode

Version Support: 5.0.0

Bridge mode is now the default connector routing method if no other routing method is explicitly stated. The bridge-mode does not use the user.map file which reflects other changes to take a more secure default deployment. A warning will be displayed during the validation process to tell you if bridge-mode is being enabled. It will not be enabled in the following cases:

Bridge mode eliminates the need to create or define users and passwords within the user.map file. Instead, the connector acts as a router connecting the network sockets between client application and MySQL servers.

Figure 6.7. Tungsten Connector Bridge Mode Architecture

Tungsten Connector Bridge Mode Architecture

Bridge mode provides a simpler method for connecting clients to MySQL, but with reduced facilities, as outline in the table below:

Feature Standard Mode Bridge Mode
Master/Slave Selection Yes Yes
Switch/Failover Yes Yes
Automatic Read/Write Splitting Yes No
Application-based Read/Write Splitting Yes Yes
Seamless Reconnects Yes No

Bridge mode connections operate as follows:

  1. Client opens network connection to Connector

  2. Connector allocates a network buffer for the client network connection to the database server

  3. Connector opens a network connection to a database server based on the connection parameters (master/slave selection)

  4. Connector allocates a network buffer for the database server to the client application

  5. Connector directly attaches the network sockets sockets together

Because the network sockets between the two sides are connected directly together, the following behavior applies to bridge mode connections:

  • User authentication is handled directly by the database server, rather than through the user.map file.

  • In the event of a failover or switch of the database servers, all active connections to the affected servers are closed.

  • Smartscale and packet inspection to provide read/write splitting are not supported, since the Connector does not access individual packet data.