I'm looking for the easiest way to build a Wildfly cluster with JMS load balancing for a development platform. Messages will be produced by the Wildfly servers themselves.
I wonder how works the ActiveMQ Artemis JMS server embedded in Wildfly in a cluster deployment. I see on this site that a Wildfly node can declare its JMS server as master or slave.
I also read here that a MDB can use an "in-vm-connector" connector.
I'm not sure that I understand how a JMS cluster works with a master and a slave JMS server with "in-vm-connector". Will the MDB instances in the Wildfly node with the slave JMS server receive messages? Will the JMS cluster provide load balancing or will there be only one active JMS server at the same time?
In ActiveMQ Artemis (i.e. the JMS broker embedded into WildFly) clustering (which provides things like message load balancing) and high-availability (which provides redundancy for the integrity of the message data) are separate concepts. The master/slave configuration you mentioned is for high-availability. This configuration doesn't provide message load balancing since only one of the brokers is alive at any given point in time.
If you want configure a master/slave pair it's recommended that you separate those servers from the servers that actually process the messages since it doesn't make sense to have MDBs running on a server which doesn't have a live broker (i.e. a slave) since they won't receive any messages.
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We are developing an application using Spring Boot and Apache Camel that is reading a message from ActiveMQ Artemis, doing some transformation, and sending it to ActiveMQ Artemis. Our application is deployed as war file in on-premise JBoss EAP 7.2.0. Both the source and target applications are remote to our application and they are also deployed on JBoss EAP 7.2.0. The remote queues to which Camel is connecting are ActiveMQ Artemis which were created in JBoss and connecting using http-remoting protocol. These setup was working when there were only one node of each of the applications.
Now we are making the source and target applications 3 nodes each (i.e. they will be deployed in multiple JBoss servers). For accessing the front-end of the source and target applications we are configuring and accessing them through a load balancer.
Can we configure the load balancer to access the source and target brokers from the Camel layer? There will be 3 source and 3 target brokers. Or is clustering the brokers the only option in this case?
We are thinking of load balancing between the queues and not clustering. Suppose we have three queues q1, q2, and q3 with corresponding brokers b1, b2, and b3. I will configure the load balancer url in the Camel layer like http-remoting://<load-balancer-url>:<port> (much like we do while load balancing HTTP API requests). Any message coming in will hit the load balancer, and the load balancer will decide which queue to route the message to.
JMS connections are stateful. When a client creates a connection there is no indication of the queues to which it will send messages. The load-balancer will have to direct that client's connection to either b1, b2, or b3 and it will have no way to determine where it should go. A load-balancer working with messaging will almost certainly only be able to balance connections, not messages. It sounds like you want load-balancing at the message level instead. Perhaps you should look into something like Qpid Dispatch Router.
Messaging doesn't use HTTP so using an HTTP load balancer like you do with your HTTP API(s) won't work. It's easy for a load-balancer to inspect HTTP headers and route requests, especially since HTTP is stateless. However, messaging connections are stateful and the protocols are typically quite a bit more complex than HTTP. I don't know of any load-balancers that will work the way you are wanting for messaging.
You need your client not to use the topology, you can do this by using "setUseTopologyForLoadBalancing" on your AMQConnectionFactory. If you get the connection factory from EAP I think this is configurable on the connection factory since EAP 7.3.
Our JMS Listener application connects to an ActiveMQ network of brokers through a load balancer, which we are told distributes connections amongst brokers in a round-robin fashion. Our spring boot application is creating a connection via the load balancer, which in turn feeds the connection to one of the brokers amongst the network of brokers. If a message is published to the brokers then it would be a lot quicker if the message was on the broker that the JMS listener connection lived on. However, the likelihood of that occurring is slim unless we can distribute the connections across the brokers.
I've tried increasing the concurrency in the DefaultJmsListenerContainerFactory, but that didn't do the trick. I was thinking about somehow extending the AbstractJmsListenerContainerFactory, and somehow create a Map of DefaultMessageListenerContainer instances but it looks like the createListenerContainer will only return an instance of whatever is parameterized in the AbstractJmsListenerContainerFactory and we cannot parameterize it with an instance of Map.
We are using Spring Boot 1.5.14.RELEASE.
== UPDATE ==
I've been playing around with the classes above, and it seems like it is inherent in Spring JMS that a Jms Listener be associated with a Single Message Listener Container, which in turn is associated with a single (potentially shared) connection.
For any folks that have JMS Application Listeners that are connecting to a load balanced network of brokers, are you creating a single connection that is connecting to a single broker, and if so, do you experience significant performance degradation as a result of the network of brokers having to move any inbound messages to a broker with consumers?
We have an application running in a GlassFish 3.1.2.2 cluster (two instances) that writes its results to "the_output_queue".
GlassFish sets up Message Queue as an embedded broker cluster, which in turn has also two message broker instances corresponding directly to the two GlassFish instances.
Now I would like to consume results from the_output_queue with an external JMS client (think Android app).
I assumed that a broker cluster can somehow be accessed transparently by a JMS client, but I cannot get this to work. I only succeed in connecting a JMS client to one individual broker.
If I have one JMS client running, connected to one broker I get only half of the messages. The physical queue (the_output_queue) defined in the GlassFish Administration Console exists in both brokers and the messages get evenly distributed thanks to load balancing.
This text from the Oracle manuals sounds to me like every message should be available in all broker instances of the cluster, i.e. if only a single JMS consumer is running it should receive all messages irrespective of the broker instance it is connected to.
"The home broker is responsible for routing and delivering the messages to all consumers of the destination, whether these consumers are local (connected to the home broker) or remote (connected to other brokers in the cluster)."
Have I misunderstood this completely?
Can a JMS client access a Oracle Message Queue broker cluster transparently?
How would the connection string look?
Is there some "global cluster target" (instead of an individual broker) to which the JMS client can connect? Where could I find the connection details for the cluster?
Is there something special in the GlassFish setup I have to verify? The settings currently are (default setup created by jelastic.com, looks good to me):
JMS Availability:
JMS Service Type: Embedded
JMS Cluster Type: Conventional
JMS Configuration Store Type: Master Broker
JMS Message Store Type: File
GMS is enabled
Answer to the main question: Yes, a JMS client can connect to any instance of a cluster and GlassFish will replicate the messages. I have tested it on my PC.
The problem in Jelastic is discussed in this posting.
I have Weblogic 10.3.4 with a cluster of 2 managed servers, each with a JMS server. I also have a clustered JMS module with several "Uniform Distributed Queue"s. I have verified via a simple Java class that my JMS cluster does work when going through a clustered t3 URL.
However, I would like to monitor these clustered JMS queues and look at their messages in the Weblogic console. I know with a non-clustered JMS setup, I can go into the JMS module, then into the JMS queue, then to Monitoring, then to "Show Messages" as I see a destination there. However, in my clustered setup, I don't see a destination in the similar location. I know that my JMS cluster does work after some effort and assistance, but is there something else I may have missed in the configuration? I would like to view the number and contents of messages in my clustered JMS setup.
I am trying to configure clustered JMS on Weblogic 10.3.4.
I have a 4 node cluster plus my AdminServer already configured. I also have my JMS already configured and targeted to AdminServer. From reading the Weblogic documentation, I am not clear as how to cluster the JMS server. Could someone please explain how?
There is no 'clustered JMS server'. There are WebLogic clusters, the Admin Server & Managed Servers and then JMS Servers. JMS Servers are a configuration construct within a Managed Server.
In order to cluster JMS in WebLogic each managed server in the cluster needs a JMS server. Then, when you create JMS resources you can either use default targeting or subdeployments. If you use default targeting then it will implicitly target the resource to the JMS server for each managed server in the cluster. If you have more than one JMS server per managed server, the behavior can be different, but you likely don't need that. Alternatively, you can use subdeployments to target specific managed servers or JMS servers, but not likely needed for your purposes.