Datasource Failover Notification

[mayankmit2002]

my Environment
--------------------

2 Postgres Servers v 8.3.1
1 JBoss AS 4.2.3

Setup
------

In my postgress-ds.xml, I've configured the datasource as HA-XA-datasource to use both servers.

Problem
---------
Now I want to get notified when one data base is down to intimate the clients that database is down.


Is there any way to listen any such JMX notification that notifies about the database failover

[babazs]

Hy!

Could you attach your postgress-ds.xml.

thx.

[mayankmit2002]

<datasources>
 <ha-xa-datasource>
 <jndi-name>PostgresDS</jndi-name>
 <xa-datasource-class>org.postgresql.xa.PGXADataSource</xa-datasource-class>
 <xa-datasource-property name="ServerName">${data.source}</xa-datasource-property>
 <xa-datasource-property name="PortNumber">5432</xa-datasource-property>
 <xa-datasource-property name="DatabaseName">smd</xa-datasource-property>
 <!--xa-datasource-property name="Ssl">false</xa-datasource-property-->
 <xa-datasource-property name="User">systemmgr</xa-datasource-property>
 <xa-datasource-property name="Password">cms10</xa-datasource-property>
 <url-property>ServerName</url-property>
 <url-delimiter>,</url-delimiter>

 <track-connection-by-tx/>

 <metadata>
 <type-mapping>PostgreSQL 8.0</type-mapping>
 </metadata>

 <prepared-statement-cache-size>32</prepared-statement-cache-size>
 <min-pool-size>5</min-pool-size>
 <max-pool-size>20</max-pool-size>
 <max-idle-timeout>0</max-idle-timeout>
 <blocking-timeout-millis>30000</blocking-timeout-millis>
 <idle-timeout-minutes>0</idle-timeout-minutes>
 <track-statements>true</track-statements>
 <check-valid-connection-sql>select version()</check-valid-connection-sql>
 </ha-xa-datasource>

 <ha-xa-datasource>
 <jndi-name>ArgusDS</jndi-name>
 <xa-datasource-class>org.postgresql.xa.PGXADataSource</xa-datasource-class>
 <xa-datasource-property name="ServerName">${data.source}</xa-datasource-property>
 <xa-datasource-property name="PortNumber">5432</xa-datasource-property>
 <xa-datasource-property name="DatabaseName">smd</xa-datasource-property>
 <!--xa-datasource-property name="Ssl">false</xa-datasource-property-->
 <xa-datasource-property name="User">systemmgr</xa-datasource-property>
 <xa-datasource-property name="Password">cms10</xa-datasource-property>
 <url-property>ServerName</url-property>
 <url-delimiter>,</url-delimiter>

 <track-connection-by-tx/>

 <metadata>
 <type-mapping>PostgreSQL 8.0</type-mapping>
 </metadata>

 <prepared-statement-cache-size>32</prepared-statement-cache-size>
 <min-pool-size>5</min-pool-size>
 <max-pool-size>20</max-pool-size>
 <max-idle-timeout>0</max-idle-timeout>
 <blocking-timeout-millis>30000</blocking-timeout-millis>
 <idle-timeout-minutes>0</idle-timeout-minutes>
 <track-statements>true</track-statements>
 <check-valid-connection-sql>select version()</check-valid-connection-sql>
 </ha-xa-datasource>

 <ha-xa-datasource>
 <jndi-name>DefaultDS</jndi-name>
 <xa-datasource-class>org.postgresql.xa.PGXADataSource</xa-datasource-class>
 <xa-datasource-property name="ServerName">${data.source}</xa-datasource-property>
 <xa-datasource-property name="PortNumber">5432</xa-datasource-property>
 <xa-datasource-property name="DatabaseName">jms</xa-datasource-property>
 <!--xa-datasource-property name="Ssl">false</xa-datasource-property-->
 <xa-datasource-property name="User">systemmgr</xa-datasource-property>
 <xa-datasource-property name="Password">cms10</xa-datasource-property>
 <url-property>ServerName</url-property>
 <url-delimiter>,</url-delimiter>

 <track-connection-by-tx/>

 <metadata>
 <type-mapping>PostgreSQL 8.0</type-mapping>
 </metadata>

 <prepared-statement-cache-size>32</prepared-statement-cache-size>
 <min-pool-size>5</min-pool-size>
 <max-pool-size>20</max-pool-size>
 <max-idle-timeout>0</max-idle-timeout>
 <blocking-timeout-millis>30000</blocking-timeout-millis>
 <idle-timeout-minutes>0</idle-timeout-minutes>
 <track-statements>true</track-statements>
 <check-valid-connection-sql>select version()</check-valid-connection-sql>
 </ha-xa-datasource>

 <ha-xa-datasource>
 <jndi-name>BMSDS</jndi-name>
 <xa-datasource-class>org.postgresql.xa.PGXADataSource</xa-datasource-class>
 <xa-datasource-property name="ServerName">${data.source}</xa-datasource-property>
 <xa-datasource-property name="PortNumber">5432</xa-datasource-property>
 <xa-datasource-property name="DatabaseName">bms</xa-datasource-property>
 <xa-datasource-property name="User">systemmgr</xa-datasource-property>
 <xa-datasource-property name="Password">cms10</xa-datasource-property>
 <url-property>ServerName</url-property>
 <url-delimiter>,</url-delimiter>

 <track-connection-by-tx/>

 <metadata>
 <type-mapping>PostgreSQL 8.0</type-mapping>
 </metadata>

 <prepared-statement-cache-size>32</prepared-statement-cache-size>
 <min-pool-size>5</min-pool-size>
 <max-pool-size>20</max-pool-size>
 <max-idle-timeout>0</max-idle-timeout>
 <blocking-timeout-millis>30000</blocking-timeout-millis>
 <idle-timeout-minutes>0</idle-timeout-minutes>
 <track-statements>true</track-statements>
 <check-valid-connection-sql>select version()</check-valid-connection-sql>
 </ha-xa-datasource>

</datasources>

[babazs]

How can you use ha-xa datasource service, these datasources are differents.

[babazs]

I would like to create the same topolgy with postgres datasources:
http://www.mastertheboss.com/en/jboss-application-server/82-jboss-datasource-ha.html

[vickyk]

"mayankmit2002" wrote:

In my postgress-ds.xml, I've configured the datasource as HA-XA-datasource to use both servers.

The attached -ds.xml contains incorrect configuration about ha datasource !

"mayankmit2002" wrote:

Problem
---------
Now I want to get notified when one data base is down to intimate the clients that database is down.

I don't know what exactly you are trying to do here.
You can write a custom MBean which will monitor the working of the datasource,getting the JMX notification when the DB goes down would not be possible without the change in JCA code.
With Jboss5 you can probabily make the JMX notification via custom UrlSelectStrategy implementation.