Single JMS server for the whole cluster - Websphere

This is a discussion on Single JMS server for the whole cluster - Websphere ; Suppose that I have several machines running websphere application server V5.1.1 in a cluster environment. I have read from IBM red book that you can have JMS servers per node in a cluster. However, I want to have a SINGLE ...

+ Reply to Thread
Results 1 to 10 of 10

Thread: Single JMS server for the whole cluster

  1. Single JMS server for the whole cluster

    Suppose that I have several machines running websphere application server V5.1.1 in a cluster environment. I have read from IBM red book that you can have JMS servers per node in a cluster. However, I want to have a SINGLE JMS Server for the whole cluster, so that when I send a message to a topic only once and not for each node, and MDBs on all Websphere instances will recieve the message.

    Can this be done, or I have to send a message to each node one by one?

  2. Re: Single JMS server for the whole cluster

    One more question.

    In a scenario where there are many instances of the application server running on a single node, and if I deploy an MDB in each of the server instance, then will each of them be having their own copy of the MDB or the MDB will be shared by all the instances?

  3. Re: Single JMS server for the whole cluster

    parthmehtaj@gmail.com wrote:
    > One more question.
    >
    > In a scenario where there are many instances of the application
    > server running on a single node, and if I deploy an MDB in each of
    > the server instance, then will each of them be having their own copy
    > of the MDB or the MDB will be shared by all the instances?



    What do you mean by 'copy'?

    If you mean executing instance of the MDB, well of course a single
    instance cannot run in multiple JVMs at the same time ...

  4. Re: Single JMS server for the whole cluster

    parthmehtaj@gmail.com wrote:
    > Suppose that I have several machines running websphere application
    > server V5.1.1 in a cluster environment. I have read from IBM red book
    > that you can have JMS servers per node in a cluster. However, I want
    > to have a SINGLE JMS Server for the whole cluster, so that when I
    > send a message to a topic only once and not for each node, and MDBs
    > on all Websphere instances will recieve the message.


    Your question doesn't make any sense.

  5. Re: Single JMS server for the whole cluster

    Yeah you are right. Sorry for the tardy question. Let me rephrase that a little bit.

    Can I have a common, single JMS server for an entire cell? instead of for a single node?

    The whole motivation behind this question was that I dont want to reference the topic on each node and send messages to them individually, but want to send mressages to a cell wide common topic, so that ALL MDBs in the cell listening to that topic will recieve that message. Good enough?

  6. Re: Single JMS server for the whole cluster

    A node is just the scope at which the JMS server is defined as that is
    where it runs. It can certainly be used by applications across the cell.

    If you deploy an application containing an MDB to a cluster then, if you
    have non-durable subscriptions, every cluster member will get a copy of
    every message, if you have durable subscriptions and the same client ID
    and subscription name for each cluster member then only one MDB instance
    in the cluster will receive each message.

    Regards,
    David

  7. Re: Single JMS server for the whole cluster

    Right so lemme understand(I am a Websphere novice ) I create a topic with cell-wide scope. But there are just 2 things i dont understand now.

    1) How do I tell the MDB to listen to THAT topic explicitly, or do I need to tell it at all?

    2) This is regarding failover. Maybe thats not a problem if I can create the same topic with the same cell-wide scope on all the machines, but then "IF" I have to configure each MDB to point to a particular node, with IP address and all, what if that machine goes down? Or I should not worry about it coz this just may not be needed?




  8. Re: Single JMS server for the whole cluster

    parthmehtaj@gmail.com wrote:
    > Right so lemme understand(I am a Websphere novice ) I create a
    > topic with cell-wide scope. But there are just 2 things i dont
    > understand now.
    >
    > 1) How do I tell the MDB to listen to THAT topic explicitly, or do I
    > need to tell it at all?


    In WAS 5.x, which is where I think you are, you configure a listener
    port to associate a destination with an MDB. In later versions, listener
    ports go away and are replaced with activation specifications.
    >
    > 2) This is regarding failover. Maybe thats not a problem if I can
    > create the same topic with the same cell-wide scope on all the
    > machines, but then "IF" I have to configure each MDB to point to a
    > particular node, with IP address and all, what if that machine goes
    > down? Or I should not worry about it coz this just may not be needed?


    Are you talking about failover of your messaging infrastructure? Or
    what? Exactly what is your JMS provider? I don't think you ever actually
    made that clear.

  9. Re: Single JMS server for the whole cluster

    I have 2 JMS providers installed.

    1)Websphere JMS Provider,
    2)Websphere MQ JMS Provider

    Yes. Thats right. Failover of the messaging infrastructure. The JMS message server to be exact. Where all my Topics and Queues are created.

  10. Re: Single JMS server for the whole cluster

    So, if you are using the embedded JMS server then you would create your
    resources on the WebSphere JMS provider. The scope at which you define
    the resources doesn't matter (so long as it includes the servers where
    they will be used). The important part is that when you create the
    connection factory you specify the node where the JMS server resides. At
    runtime this node name is used to find the appropriate host and port for
    the JMS server. If the JMS server goes down then the MDBs will stop
    receiving messages and enter a retry loop trying to reconnect to the JMS
    server.

    Regards,
    David

+ Reply to Thread