Setting up IBM DB2

The following sections describe how to replace the default H2 databases with IBM DB2:

Prerequisites

Download the latest version of DB2 Express-C and install it on your computer.

For instructions on installing DB2 Express-C, see this ebook.

Setting up the database and users

Create the database using either DB2 command processor or DB2 control center as described below.

Using the DB2 command processor

Run DB2 console and execute the db2start command in CLI to open DB2.
Create the database using the following command:
create database <DB_NAME>
Before issuing a SQL statement, establish the connection to the database using the following command:
connect to <DB_NAME> user <USER_ID> using <PASSWORD>
Grant required permissions for users as follows:
```
connect to DB_NAME
grant <AUTHORITY> on database to user <USER_ID>
```
For example:

For more information on DB2 commands, see the DB2 Express-C Guide.

Using the DB2 control center

Open the DB2 control center using the db2cc command as follows:
Right-click All Databases in the control center tree (inside the object browser), click Create Database, and then click Standard and follow the steps in the Create New Database wizard.
Click User and Group Objects in the control center tree to create users for the newly created database.
Give the required permissions to the newly created users.

Setting up DB2 JDBC drivers

Copy the DB2 JDBC drivers (db2jcc.jar and db2jcc_license_c0u.jar) from <DB2_HOME>/SQLLIB/java/ directory to the <PRODUCT_HOME>/repository/components/lib/ directory.

<DB2_HOME> refers to the installation directory of DB2 Express-C, and <PRODUCT _HOME> refers to the directory where you run the WSO2 product instance.

Setting up datasource configurations

A datasource is used to establish the connection to a database. By default, WSO2_CARBON_DB datasource is used to connect to the default H2 database, which stores registry and user management data. After setting up the IBM DB2 database to replace the default H2 database, either change the default configurations of the WSO2_CARBON_DB datasource, or configure a new datasource to point it to the new database as explained below.

Changing the default WSO2_CARBON_DB datasource

Follow the steps below to change the type of the default WSO2_CARBON_DB datasource.

Edit the default datasource configuration in the <PRODUCT_HOME>/repository/conf/datasources/m aster-datasources.xml file as shown below.

<datasource>
      <name>WSO2_CARBON_DB</name>
      <description>The datasource used for registry and user manager</description>
      <jndiConfig>
            <name>jdbc/WSO2CarbonDB</name>
      </jndiConfig>
      <definition type="RDBMS">
            <configuration>
                <url>jdbc:db2://SERVER_NAME:PORT/DB_NAME</url>
                <username>regadmin</username>
                <password>regadmin</password>
                <driverClassName>com.ibm.db2.jcc.DB2Driver</driverClassName>
                <maxActive>80</maxActive>
                <maxWait>360000</maxWait>
                <minIdle>5</minIdle>
                <testOnBorrow>true</testOnBorrow>
                <validationQuery>SELECT 1</validationQuery>
                <validationInterval>30000</validationInterval>
				<defaultAutoCommit>false</defaultAutoCommit>
            </configuration>
      </definition>
</datasource>

The elements in the above configuration are described below:

Element	Description
url	The URL of the database. The default port for a DB2 instance is 50000.
username and password	The name and password of the database user
driverClassName	The class name of the database driver
maxActive	The maximum number of active connections that can be allocated at the same time from this pool. Enter any negative value to denote an unlimited number of active connections.
maxWait	The maximum number of milliseconds that the pool will wait (when there are no available connections) for a connection to be returned before throwing an exception. You can enter zero or a negative value to wait indefinitely.
minIdle	The minimum number of active connections that can remain idle in the pool without extra ones being created, or enter zero to create none.
testOnBorrow	The indication of whether objects will be validated before being borrowed from the pool. If the object fails to validate, it will be dropped from the pool, and another attempt will be made to borrow another.
validationQuery	The SQL query that will be used to validate connections from this pool before returning them to the caller.
validationInterval	The indication to avoid excess validation, and only run validation at the most, at this frequency (time in milliseconds). If a connection is due for validation, but has been validated previously within this interval, it will not be validated again.
defaultAutoCommit	This property is not applicable to the Carbon database in WSO2 products because auto committing is usually handled at the code level, i.e., the default auto commit configuration specified for the RDBMS driver will be effective instead of this property element. Typically, auto committing is enabled for an RDBMS drivers by default. When auto committing is enabled, each SQL statement will be committed to the database as an individual transaction, as opposed to committing multiple statements as a single transaction.

For more information on other parameters that can be defined in the <PRODUCT_HOME>/repository/conf/datasources/ master-datasources.xml file, see Tomcat JDBC Connection Pool.

Configuring new datasources to manage registry or user management data

Follow the steps below to configure new datasources to point to the new databases you create to manage registry and/or user management data separately.

Add a new datasource with similar configurations as the WSO2_CARBON_DB datasource above to the < PRODUCT_HOME>/repository/conf/datasources/ master-datasources.xml file. Change its elements with your custom values. For instructions, see Setting up datasource configurations.
If you are setting up a separate database to store registry-related data, update the following configurations in the <PRODUCT_HOME>/repository/conf/ registry.xml file.
```
<dbConfig name="wso2registry">
	<dataSource>jdbc/MY_DATASOURCE_NAME</dataSource>
</dbConfig>
```
If you are setting up a separate database to store user management data, update the following configurations in the <PRODUCT_HOME>/repository/conf/ user-mgt.xml file.
```
<Configuration>
	<Property name="dataSource">jdbc/MY_DATASOURCE_NAME</Property>
</Configuration>
```

Creating database tables

To create the database tables, connect to the database that you created earlier and run the following scripts in the DB2 Express-C command editor.

To create tables in the registry and user manager database (WSO2CARBON_DB), use the below script:
```
<PRODUCT_HOME>/dbscripts/db2.sql
```
Restart the server.

You can create database tables automatically when starting the product for the first time by using the -Dsetup parameter as follows:

For Windows: <PRODUCT_HOME>/bin/wso2server.bat -Dsetup
For Linux: <PRODUCT_HOME>/bin/wso2server.sh -Dsetup