If you have a mirrored SQL cluster but it has no VIP (virtual IP), and you want to connect a DualShield server to the SQL cluster for the purpose of failover redundancy. How can it be achieved?

DualShield Authentication Server utilizes JDBC driver to connect to a SQL server. You can achieve it by adding both servers to the JDBC connection string.

The JDBC string is found in the file named "server.xml" located in the "c:\program files\deepnet dualshield\tomcat\conf" folder.

Let us look at an example below that connects to one MySQL server. 

<Resource name="jdbc/DasDS" driverClassName="com.mysql.jdbc.Driver" maxIdle="2" password="changeit" url="jdbc:mysql://localhost:3306/dualshield?useUnicode=true&amp;characterEncoding=UTF-8" username="root" maxActive="1000" type="javax.sql.DataSource" validationQuery="Select 1" maxWait="5000">

To support a failover cluster, you need to change the JDBC string to:

<Resource name="jdbc/DasDS" driverClassName="com.mysql.jdbc.Driver" maxIdle="2" password="changeit" url="jdbc:mysql://localhost,192.168.124.201:3306/dualshield?useUnicode=true&amp;failOverReadOnly=false&amp;characterEncoding=UTF-8" username="root" maxActive="1000" validationQuery="Select 1" maxWait="5000" type="javax.sql.DataSource">

As you can see, we appended the second SQL server after the original one "localhost" separated with a comma, e.g. "localhost,192.168.124.201"

In addition, you also need to set the failover property:

failOverReadOnly=false

(its default value was true), otherwise you will get an error "connection is read-only. Queries leading to data modification are not allowed". MS SQL and ORACLE have similar failover settings in their JDBC connection strings. In MS SQL, it is called "failoverPartner"

References

https://dev.mysql.com/doc/connector-j/5.1/en/connector-j-config-failover.html