Datasource mysql failover - howto configure? - spring

Question

I'm using a spring project with org.apache.commons.dbcp.BasicDataSource datasource.
If i want my Database to support a failover where do i configure it?
I cant find any references with google

Answer 1

You were a bit generic in the question. I describe some possible solutions.
If you can use c3p0 here is an example with mysql server.
In the tomcat server.xml define this:
<Resource
name="jdbc/trm"
type="com.mchange.v2.c3p0.ComboPooledDataSource"
driverClass="com.microsoft.sqlserver.jdbc.SQLServerDriver"
password="password"
user="username"
auth="Container"
description="DB Connection pool for TRM application"
minPoolSize="2"
maxPoolSize="4"
acquireIncrement="1"
factory="org.apache.naming.factory.BeanFactory"
jdbcUrl=jdbc:mysql://localhost:3306,backupdb.something.com:3306/dbname
preferredTestQuery="SELECT 'Connection' = 'true'"
testConnectionOnCheckout="true"
/>
In case of sql server replace
jdbcUrl=jdbc:mysql://localhost:3306,backupdb.something.com:3306/dbname
with
jdbcUrl="jdbc:sqlserver://mainserver:1433;failoverPartner=backupserver;databaseName=nameofyourdatabase;applicationName=appname"
In case of oracle another solution is recomended. I just give you the link to the offical spring documentation:
http://static.springsource.org/spring-data/jdbc/docs/current/reference/html/orcl.failover.html
and I just copy here the spring bean to be used for completness.
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:orcl="http://www.springframework.org/schema/data/orcl"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.0.xsd
http://www.springframework.org/schema/data/orcl
http://www.springframework.org/schema/data/orcl/spring-data-orcl-1.0.xsd">
<orcl:pooling-datasource id="racDataSource"
url="jdbc:oracle:thin:#(description=(address_list=
(address=(host=rac1)(protocol=tcp)(port=1521))
(address=(host=rac2)(protocol=tcp)(port=1521)))
(connect_data=(service_name=racdb1)))"
properties-location="classpath:orcl.properties"
fast-connection-failover-enabled="true" 1
ONS-configuration="rac1:6200,rac2:6200"/> 2
<bean id="transactionManager"
class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
<property name="dataSource" ref="racDataSource"/>
</bean>
</beans>
Other approaches are possible. E.g. using the AbstractRoutingDataSource offered from springframework.