database failover for ejb application (persistance.xml probl

[grdzeli_kaci]

hi all,
i tried to use database failover by ha-xa-datasource.
my database configuration file looks like :
1.oracle-ha-xa-ds.xml

<datasources>
 <ha-xa-datasource>
 <jndi-name>XAOracleDS</jndi-name>
 <track-connection-by-tx/>
 <isSameRM-override-value>false</isSameRM-override-value>
 <xa-datasource-class>oracle.jdbc.xa.client.OracleXADataSource</xa-datasource-class>
 <!-- list of connection URLs -->
 <xa-datasource-property name="URL">jdbc:oracle:thin:@192.168.9.135:1521:DEVSTR|jdbc:oracle:thin:@192.9.200.222:1521:DEVSTR</xa-da
 <xa-datasource-property name="User">USER_MANAGER</xa-datasource-property>
 <xa-datasource-property name="Password">USER_MANAGER</xa-datasource-property>
 <url-property>URL</url-property>
 <url-delimeter>|</url-delimeter>
 <valid-connection-checker-class-name>tempPackage.OracleValidConnectionChecker</valid-connection-checker-class-name>
 <exception-sorter-class-name>tempPackage.OracleExceptionSorter</exception-sorter-class-name>
 </ha-xa-datasource>
</datasources>

bu ti can't use this configuration into my ejb application,
is there any doc or example how to config my persistance.xml in this case ????
my persistance.xml looks like :
2.persistance.xml

<?xml version="1.0" encoding="ISO-8859-1" ?>
<persistence xmlns="http://java.sun.com/xml/ns/persistence"
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd"
 version="1.0">
 <persistence-unit name="Test">
 <provider>org.hibernate.ejb.HibernatePersistence</provider>
 <non-jta-data-source>java:/XAOracleDS</non-jta-data-source>
 <properties>
 <property name="hibernate.hbm2ddl.auto" value="validate"/>
 <property name="hibernate.cache.provider_class" value="org.hibernate.cache.HashtableCacheProvider"/>
 <property name="hibernate.default_schema" value="USER_MANAGER"/>
 </properties>
 </persistence-unit>
</persistence>

i tried to use jta-data-source instead of non-jta-data-source but i got the errors :
1.non-jta-datasource:

java.lang.RuntimeException: You have not defined a jta-data-source for a JTA enabled persistence context named: Test
 at org.jboss.ejb3.entity.PersistenceUnitDeployment.start(PersistenceUnitDeployment.java:220)
 at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
 at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
 at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
 at java.lang.reflect.Method.invoke(Method.java:597)
 at org.jboss.ejb3.ServiceDelegateWrapper.startService(ServiceDelegateWrapper.java:103)
 at org.jboss.system.ServiceMBeanSupport.jbossInternalStart(ServiceMBeanSupport.java:289)
 at org.jboss.system.ServiceMBeanSupport.jbossInternalLifecycle(ServiceMBeanSupport.java:245)
 at sun.reflect.GeneratedMethodAccessor3.invoke(Unknown Source)
 at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)

2. jta-datasource:

09:20:28,571 WARN [JBossManagedConnectionPool] Throwable while attempting to get a new connection: null
org.jboss.resource.JBossResourceException: Missing configuration for HA XA datasource. No url-delimiter.
 at org.jboss.resource.adapter.jdbc.xa.HAXAManagedConnectionFactory.createManagedConnection(HAXAManagedConnectionFactory.java:97)
 at org.jboss.resource.connectionmanager.InternalManagedConnectionPool.createConnectionEventListener(InternalManagedConnectionPool.java:577)
 at org.jboss.resource.connectionmanager.InternalManagedConnectionPool.getConnection(InternalManagedConnectionPool.java:262)

i fount documentations how to write database failover configuration file but i can't find anything about persistance.xml :( how i can use it into my ejb application ?

any idea will be appreciated.


Thanks In Advance.
_________________
Paata,

[vickyk]

4.2 Changes
As of JBoss 4.2.x the url-delimeter property has been updated to fix the typo. The property is now correctly named url-delimiter.

Read this from the following link
http://wiki.jboss.org/wiki/Wiki.jsp?page=JBossJCADatabaseFailover

So verify what version of the Jboss are you running ?

[grdzeli_kaci]

"vickyk" wrote:

4.2 Changes
As of JBoss 4.2.x the url-delimeter property has been updated to fix the typo. The property is now correctly named url-delimiter.

Read this from the following link
http://wiki.jboss.org/wiki/Wiki.jsp?page=JBossJCADatabaseFailover

So verify what version of the Jboss are you running ?

.
hah, sorry :(
great thanks vickyk,
i know this link but i did not read it to the end.


it works :)
Thanks again.

[grdzeli_kaci]

hi again,
i have another question about failover,
i want switch database manually, all databasese for jboss are working but i want switch manually from one to another.
is it possible ?

[vickyk]

"grdzeli_kaci" wrote:
hi again,
i have another question about failover,
i want switch database manually, all databasese for jboss are working but i want switch manually from one to another.
is it possible ?

What do you mean by manually ?
I think you need to handle this from the application code ....

Have a look at these
http://jira.jboss.com/jira/browse/JBAS-3707
http://www.jboss.com/index.html?module=bb&op=viewtopic&t=110391&start=10

The pointed JIRA is already available in the Jboss5 trunk .
[/url]

[grdzeli_kaci]

great thanks vickyk for your posts,
i have message driven bean, and if i got some message i want to switch database, message contains information which database must i use?
is it possible ?

i will read yuor links, Thanks,

[vickyk]

"grdzeli_kaci" wrote:

i have message driven bean, and if i got some message i want to switch database, message contains information which database must i use?
is it possible ?

This needs to be controlled at the application code level .

[grdzeli_kaci]

i think you mean that i can write SampleUrlSelector class and put into the $JBOSS_HOME/server/default/lib directory,
am i right ?
as you told on this topic :
http://www.jboss.com/index.html?module=bb&op=viewtopic&t=110391&postdays=0&postorder=asc&start=10

All you need is to have the following configuration at the ManagedConnectionFactory setting
Code:

<url-selector-strategy-class-name>org.demo.SampleUrlSelector</url-selector-strategy-class-name>



This is the entry you need to place in the -ds.xml file .
Right now I am not able to find the samples where I had tried it , I will give it a test this weekend and probabily update the wiki .

Also make sure that your custom code is made available to the server . You can jar it and drop it in the $JBOSS_HOME/server/default/lib directory .

can you game me this class : SampleUrlSelector ?

how i can call this class from my MDB bean ?
:( it is very bad that if this is not working with jboss 4.2.1.GA :(,

It is done in Jboss 5

jboss 5 is not release and it is not good idea to use it in production :(

great thanks in advance.

[vickyk]

you don't need URLSelectorStrategy , you need to handle the switching of appropriate DS in your MDB . Now you need to do your OWN HOMEWORK :) , I am not going to help you writing the application code !!!!

[grdzeli_kaci]

thank you,
i don't want that you help me to write my application code.
simple, i need to understand.
ok, i will not use URLSelectorStrategy.
how i can handle switching of appropriate DS?
may i use ha-xa-datasources and implement ConnectionChecker and ExceptionSorter classes or simple add multiple DS into my -ds.xml file ?

[grdzeli_kaci]

i can't fount and documentations about it :(,
if you know please post it.

[vickyk]

"grdzeli_kaci" wrote:

may i use ha-xa-datasources and implement ConnectionChecker and ExceptionSorter classes or simple add multiple DS into my -ds.xml file ?

You are completely going in a wrong direction
All you have to do is to configure multiple DS in JBoss which can be done by having multiple -ds.xml file .
In the MDB onMessage() you would need to have

onMessage(...){
InitialContext context = new InitialContext();
DataSource ds ;
if(condition1)
ds=(DataSource)context.lookup("ds1");
else if(condition2)
ds=(DataSource)context.lookup("ds1");
......................
}

You finally made me help in DOING Code for you :(

[vickyk]

"vickyk" wrote:

"grdzeli_kaci" wrote:

may i use ha-xa-datasources and implement ConnectionChecker and ExceptionSorter classes or simple add multiple DS into my -ds.xml file ?

You are completely going in a wrong direction
All you have to do is to configure multiple DS in JBoss which can be done by having multiple -ds.xml file .

Ah .... yes you were right ... I over looked you earlier statement as the first part of it was not making sense ....
you need "add multiple DS into my -ds.xml file"

[grdzeli_kaci]

yap,
i understand what you say but i think that this is not good way,
i have approximately 100 session bean where i use data sources.

do you think that if i did what you say into onMessage and then all sesssion beans get datasources from this message driven ben is good idea ???

i thought that is is possible to change anything in ha-xa-datasource and i could manage datasources.


and anyway, why i cannot have one -ds.xml file which contains mutiple datasources ??? i have multiple database but all of them are the same vendor : Oracle .
i think there is no problem if i have one -ds.xml file.


______________
Regards
Paata.

[vickyk]

"grdzeli_kaci" wrote:

i thought that is is possible to change anything in ha-xa-datasource and i could manage datasources.

ha-xa-datasource is basically used for load balancing at the Jboss side .
If you are trying to implement your custom load balancer logic then implementing URLSelector strategy would be fine .
If switching of the ds in your application is specific to your business logic then implementing URLSelector does not make sense although you can have the BL implemented in URLSelector implementation which would be disaster.