JMS Bridge Creation and configuration

JMS Bridge Creation and configuration

In this chapter I will be giving a basic idea about JMS bridge creation and configuration.

What is a JMS bridge and why JMS bridge?

JMS bridge enables you to connect between to Messaging server.

The main advantage of bridge over SAF(Store and Forward which is a WebLogic implemented Messaging Implementation) is that its server independent.

That is you can have the JMS bridge configured to connect between, WebLogic and MQ or Weblogic and JBoss etc. Although SAF can used to connect between two WebLogic servers.

HOW JMS BRIDGE CONFIGURED AND HOW IT IS ABLE TO CONNECT TO OTHER MESSAGING SERVER.

Configuring a JMS bridge is very easy, provided you have proper destination.

In a JMS bridge mainly two connections are made,

   

1) To the Source

2) To the Destination.

We can make the connection XA or non-XA, depending on the requirement and respective resource adaptor with respect to weblogic will be installed.

There are two types of adaptor

jms-xa-adp.rar     :--or which the jndi name will be "eis.jms.WLSConnectionFactoryJNDIXA"

jms-notran-adp.rar :--- for which the jndi name will be "eis.jms.WLSConnectionFactoryJNDINoTX"

Below are the steps for creating the JMS bridge

When you click Bridge from the Admin console you willget below menu

As the above picture shows a Bridge needs a Name, Source Bridge Destination and Target Bridge Destination.

Source bridge destination is from where the messages are picked up and target bridge destination is where the messages are posted to.

**One main feature of bridge is that the communication is uni-directional, i.e. On a single bridge you can’t have source bridge to receive messages from a target bridge.

If you want bi-directional communication you need to configure 2 bridges.(One for sending and other for receiving).

This is the main difference between SAF and Bridge as in SAF you can send and receive messages with one SAF agent.

Now let’s start the configuration.

When you try the create a JMS bridge below screen will appear.

Where you need to give a bridge name and Quality of Service(QOS).

QOS will determine service quality of messaging bridge.

When you are using XA transaction’s, it is always recommended to use Exactly once, which will envelops a received message and sends it within a user transaction (XA/JTA).

When you use Exactly_once mode then it ensures that the message is send only once and will rollback if there is any issue occurs during the message flow. This ensures that message will reach if the client is up and will roll back if there is any issue. Either way the message is secure are can’t be lost.

The other two QOS state are Atmost-once and Duplicate-okay. These are mainly recommended for non-XA messages.

Atmost-once :-  the resource adapter uses the AUTO_ACKNOWLEDGE mode(It will be send only once and doesn’t wait for the receiver to send a acknowledgement, which can cause message lost)

Duplicate-okay :- uses CLIENT_ACKNOWLEDGE(where there is a chance of having duplicate messages).

When you click next you see below page where you need to configure/select(if its already there) the Source Destination.

When I click “New Destination” I will get below page.

In the above page you need to add “connection url” ,”connection factory JNDI Name” and “Destination JNDI Name”

Example values

Connection_url :- t3://localhost:7001

Connection factory jndi :-  cf

Destination jndi :- “jndi configured for Queue or Topic”

The first column is the name of the Source bridge(which you give user specific if needed ) and second is the JNDI adaptor name.

As I mentioned in the beginning you can choose two adaptors, XA or non-XA

Similar for Destination

That's it with the Bridge Creation.

Now if you click bridge --> Monitoring you will be able to see the state of both Source and Destination Bridge.

Ideally if all lookup and configuration is correct the you will be seeing "Forwarding Messages".

If you start the bridge from the admin console, can will be seeing "Started by Administrator"

As we all know this will not work at when you are trying first time. So below are the main issue you could encounter.

1) Failed to connect to Source

2) Failed to connect to Destination.

If you see any above error in the "Monitoring tab" of Bridge, then the message flow will not work.

The main reason for the above issue will be the parameter that you have given in anyone of the below

“connection url” ,”connection factory JNDI Name” or “Destination JNDI Name”

Make sure you have given the connection url in the below format

“t3://localhost:7001”.

If you want to connect to multiple IP’s then you can give the url like below

“t3://<First IP Address>:<Port>,<Second IP Address>,<Port>

Also make sure the jndi names of connection factory and Queue or Topic, which you provided in the source and destination are correct.

It’s always recommended to restart the servers if you have changed any above parameters, so that binding will be refreshed.

In the logs if you see any exception with is mentioning  “eis.jms.WLSConnectionFactoryJNDIXA" or "eis.jms.WLSConnectionFactoryJNDINoTX" then it will be a problem with the adaptor.

Whenever you configure a XA or non-XA bridge to a server or a cluster of servers a file called jms-xa-adp.rar (for XA) or jms-notran-adp.rar(for non-XA) will be deployed automatically.

Make sure the files are in Active state in the “Deployment tab” at the Admin Console  and its targeted to correct servers where the bridge resides.