Messaging

Professional Open Source™

JBossMQ Messaging, JMS, JBossMQ Architecture, Advanced Configuration and Tuning

© JBoss, Inc. 2003-2005.

8/2/2005

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Topics Professional Open Source™

Messaging and JMS – The Need for Messaging – JMS API and Programming Models – JMS and Reliability

JBossMQ – – – – –

Architectural Overview The Inflow of a message through JBossMQ JBossMQ Components JBossMQ Configuration JBossMQ Fine Tuning

High Availability JBossMQ JMS and JBossMQ Anti-Patterns – How NOT to use JBossMQ

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The Need for Messaging Professional Open Source™

The integration of heterogeneous applications can be done via File Transfer – One application writes to a file and another application reads from the file. The applications need to agree on location, format and timing.

Shared Database – Multiple applications share the same database schema and a single physical database.

Remote Procedure Invocation – One application exposes functionality that can be accessed remotely and synchronously.

Messaging – One application sends a message to a provider, another application asynchronously reads the message from the provider at a later time.

Web Services 3

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Messaging Pros Professional Open Source™

Efficient use of resources – Invocations are asynchronous, no thread blocks waiting for the other party to answer. – Fire-and-forget strategy.

Reduced interface dependencies between components – The components do not need to know the RPC interfaces of their counterparts.

Functional decoupling – Allow an application to run without all components being available at the same time. – The messaging system stores the messages in transit.

Reliable communication – The messaging system provides guaranteed delivery, once and only once.

Support for multiple senders and receivers – Allow for n-ary communication.

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Messaging Cons Professional Open Source™

More complicated programming model – More verbose API than RPC’s. – More configuration issues to deal with.

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Java Message Service Professional Open Source™

The Java API that allows applications to create, send, receive and read messages Defines a common set of interfaces and the associated semantics Integral part of J2EE Supports two messaging domains – Point-to-Point (Queues) – Publish/Subscribe (Topics)

… and a cross between these domains – Topics with Durable Subscriptions

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JMS Messaging Domains Professional Open Source™

Message Sender Sender

m1

m7 m7 se

Receiver Receiver

Queue Queue

nd

Sender Sender

m6 m5 m4 m3

rec

eiv

e

Receiver Receiver

m2 re

Sender Sender

ce

iv

Receiver Receiver

m1

Message Sender Sender

e

m1 se

e rec

Topic Topic

nd

Sender Sender

Receiver Receiver

iv e

m1 Receiver Receiver

receive

m1 Sender Sender

re

ce

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Receiver Receiver

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The JMS API Professional Open Source™

QueueConnectionFactory QueueConnectionFactory

ConnectionFactory ConnectionFactory

creates

creates

QueueConnection QueueConnection

TopicConnection TopicConnection

creates

QueueSession QueueSession

creates

Session Session creates

QueueSender QueueSender

creates

Connection Connection

creates

creates

TopicConnectionFactory TopicConnectionFactory

QueueReceiver QueueReceiver

creates

TopicSession TopicSession creates

MessageProducer MessageProducer

creates

creates

MessageConsumer MessageConsumer TopicPublisher TopicPublisher TopicSubscriber TopicSubscriber creates

Message Message

Queue Queue

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Destination Destination

Topic Topic

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Reliability and JMS Professional Open Source™

The Acknowledgement Option – Two different acknowledgment sequences: the JMS provider acknowledges reception , the receiver acknowledges delivery. – AUTO_ACKNOWLEDGE, CLIENT_ACKNOWLEDGE, DUPS_OK_ACKNOWLEDGE

The Delivery Mode – Defined on a per-message basis. – PERSISTENT, NON_PERSISTENT

The Destination Type – Queues: the message is always delivered. – Topics: the subscribers that are not connected may lose messages. – Topics with Durable Subscriptions: a combination between PtoP and Pub/Sub.

Transactional Behavior – A session can be transacted or not.

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© JBoss, Inc. 2003-2005.

JBossMQ Features Professional Open Source™

JBoss 4.x supports the JMS1.1 version of the specifications JBoss 3.2.x supports the JMS1.0.2b version of the specifications JBossMQ Features – Fire-and-forget for asynchronous delivery – Guaranteed Delivery using persistent messages and durable subscriptions – Dead Letter Queue (DLQ) – Pluggable Invocation Layers to support different transport protocols (TCP/IP, HTTP, in-memory invocations) – Pluggable Security – Pluggable Persistence – JTA XA integration used by JBoss’ JMS resource adapter – High Availability in a clustered environment

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JBossMQ – An Architectural Overview Professional Open Source™

ConnectionFactory ConnectionFactory

Connection Connection

UIL2 UIL2 Service Service

Invoker Invoker

Consumer Consumer

TracingInterceptor Interceptor Tracing

Unified Invocation Layer

Session Session

ServerSecurityInterceptor ServerSecurityInterceptor

Producer Producer

HTTP HTTPIL IL Service Service JMSQueue JMSQueue

….. JMSDestination JMSDestination Manager Manager

JMSTopic JMSTopic

MDB MDB Container Container

JMSTopic JMSTopic

JVM JVMIL IL Service Service

Remote Client VM Security Security Manager Manager

JaasSecurityManager JaasSecurityManager

State State Manager Manager

Message Message Cache Cache

Persistence Persistence Manager Manager

JBossMQ VM

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© JBoss, Inc. 2003-2005.

The inflow of a message through JBossMQ Professional Open Source™

We will describe in detail JBossMQ architectural elements, by following a JMS message sent by a remote client to a MDB that subscribed to a topic.

During the walkthrough, we will insist on …

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The inflow of a message through JBossMQ Professional Open Source™ 1. Sending the message on the client side ConnectionFactory ConnectionFactory

UIL2 UIL2 Service Service

Connection Connection

Invoker Invoker

Consumer Consumer

TracingInterceptor Interceptor Tracing

Unified Invocation Layer

Session Session

ServerSecurityInterceptor ServerSecurityInterceptor

Producer Producer

HTTP HTTPIL IL Service Service JMSQueue JMSQueue

….. JMSDestination JMSDestination Manager Manager

JMSTopic JMSTopic

MDB MDB Container Container

JMSTopic JMSTopic

JVM JVMIL IL Service Service

Remote Client VM Security Security Manager Manager

JaasSecurityManager JaasSecurityManager

State State Manager Manager

Message Message Cache Cache

Persistence Persistence Manager Manager

JBossMQ VM

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© JBoss, Inc. 2003-2005.

The inflow of a message through JBossMQ Professional Open Source™ 2. The ConnectionFactory. - How does it get bound in JNDI?

ConnectionFactory ConnectionFactory

Unified Invocation Layer

Session Session

Connection Connection

UIL2 UIL2 Service Service

Invoker Invoker

Consumer Consumer

TracingInterceptor Interceptor Tracing

Producer Producer

HTTP HTTPIL IL Service Service ServerSecurityInterceptor ServerSecurityInterceptor

1. Sending the message on the client side

JMSQueue JMSQueue

….. JMSDestination JMSDestination Manager Manager

JMSTopic JMSTopic

MDB MDB Container Container

JMSTopic JMSTopic

JVM JVMIL IL Service Service

Remote Client VM Security Security Manager Manager

JaasSecurityManager JaasSecurityManager

State State Manager Manager

Message Message Cache Cache

Persistence Persistence Manager Manager

JBossMQ VM © JBoss, Inc. 2003-2005.

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The inflow of a message through JBossMQ Professional Open Source™ 2. The ConnectionFactory. - How does it get bound in JNDI?

ConnectionFactory ConnectionFactory

Unified Invocation Layer

Session Session

UIL2 UIL2 Service Service

Connection Connection

Invoker Invoker

Consumer Consumer

TracingInterceptor Interceptor Tracing

Producer Producer

HTTP HTTPIL IL Service Service ServerSecurityInterceptor ServerSecurityInterceptor

1. Sending the message on the client side

JMSQueue JMSQueue

….. JMSDestination JMSDestination Manager Manager

JMSTopic JMSTopic

MDB MDB Container Container

JMSTopic JMSTopic

JVM JVMIL IL Service Service

Remote Client VM Security Security Manager Manager 3. The Invocation Layers. - How do they work? - How to deploy them? - How to configure them? - How to secure them?

JaasSecurityManager JaasSecurityManager

State State Manager Manager

Message Message Cache Cache

Persistence Persistence Manager Manager

JBossMQ VM

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© JBoss, Inc. 2003-2005.

The inflow of a message through JBossMQ Professional Open Source™ 2. The ConnectionFactory. - How does it get bound in JNDI?

ConnectionFactory ConnectionFactory

HTTP HTTPIL IL Service Service

Unified Invocation Layer

Session Session

Connection Connection

UIL2 UIL2 Service Service

Invoker Invoker

Consumer Consumer

TracingInterceptor Interceptor Tracing

Producer Producer

4. The Invoker and the interceptor chain

ServerSecurityInterceptor ServerSecurityInterceptor

1. Sending the message on the client side

JMSQueue JMSQueue

….. JMSDestination JMSDestination Manager Manager

JMSTopic JMSTopic

MDB MDB Container Container

JMSTopic JMSTopic

JVM JVMIL IL Service Service

Remote Client VM Security Security Manager Manager 3. The Invocation Layers. - How do they work? - How to deploy them? - How to configure them? - How to secure them?

JaasSecurityManager JaasSecurityManager

State State Manager Manager

Message Message Cache Cache

Persistence Persistence Manager Manager

JBossMQ VM © JBoss, Inc. 2003-2005.

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The inflow of a message through JBossMQ Professional Open Source™ 2. The ConnectionFactory. - How does it get bound in JNDI?

ConnectionFactory ConnectionFactory

HTTP HTTPIL IL Service Service

Unified Invocation Layer

Session Session

UIL2 UIL2 Service Service

Connection Connection

Invoker Invoker

Consumer Consumer

TracingInterceptor Interceptor Tracing

Producer Producer

4. The Invoker and the interceptor chain

ServerSecurityInterceptor ServerSecurityInterceptor

1. Sending the message on the client side

JMSQueue JMSQueue

….. JMSDestination JMSDestination Manager Manager

JMSTopic JMSTopic

MDB MDB Container Container

JMSTopic JMSTopic

JVM JVMIL IL Service Service

Remote Client VM Security Security Manager Manager 3. The Invocation Layers. - How do they work? - How to deploy them? - How to configure them? - How to secure them?

JBossMQ VM

State State Manager Manager

JaasSecurityManager JaasSecurityManager 5. Configuring the JBossMQ security

Message Message Cache Cache

Persistence Persistence Manager Manager

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© JBoss, Inc. 2003-2005.

The inflow of a message through JBossMQ Professional Open Source™ 2. The ConnectionFactory. - How does it get bound in JNDI?

ConnectionFactory ConnectionFactory

6. The DestinationManager

HTTP HTTPIL IL Service Service

Unified Invocation Layer

Session Session

Connection Connection

UIL2 UIL2 Service Service

Invoker Invoker

Consumer Consumer

TracingInterceptor Interceptor Tracing

Producer Producer

4. The Invoker and the interceptor chain

ServerSecurityInterceptor ServerSecurityInterceptor

1. Sending the message on the client side

JMSQueue JMSQueue

….. JMSDestination JMSDestination Manager Manager

JMSTopic JMSTopic

MDB MDB Container Container

JMSTopic JMSTopic

JVM JVMIL IL Service Service

Remote Client VM Security Security Manager Manager 3. The Invocation Layers. - How do they work? - How to deploy them? - How to configure them? - How to secure them?

JBossMQ VM © JBoss, Inc. 2003-2005.

State State Manager Manager

JaasSecurityManager JaasSecurityManager 5. Configuring the JBossMQ security

Message Message Cache Cache

Persistence Persistence Manager Manager

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The inflow of a message through JBossMQ Professional Open Source™ 2. The ConnectionFactory. - How does it get bound in JNDI?

ConnectionFactory ConnectionFactory

Unified Invocation Layer

Session Session

UIL2 UIL2 Service Service

Connection Connection

7. Deploying a destination 6. The DestinationManager

HTTP HTTPIL IL Service Service

Invoker Invoker

Consumer Consumer

TracingInterceptor Interceptor Tracing

Producer Producer

4. The Invoker and the interceptor chain

ServerSecurityInterceptor ServerSecurityInterceptor

1. Sending the message on the client side

JMSQueue JMSQueue

….. JMSDestination JMSDestination Manager Manager

JMSTopic JMSTopic

MDB MDB Container Container

JMSTopic JMSTopic

JVM JVMIL IL Service Service

Remote Client VM Security Security Manager Manager 3. The Invocation Layers. - How do they work? - How to deploy them? - How to configure them? - How to secure them?

JBossMQ VM

State State Manager Manager

JaasSecurityManager JaasSecurityManager 5. Configuring the JBossMQ security

Message Message Cache Cache

Persistence Persistence Manager Manager

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© JBoss, Inc. 2003-2005.

The inflow of a message through JBossMQ Professional Open Source™ 2. The ConnectionFactory. - How does it get bound in JNDI?

ConnectionFactory ConnectionFactory

Unified Invocation Layer

Session Session

Connection Connection

UIL2 UIL2 Service Service

7. Deploying a destination 6. The DestinationManager

HTTP HTTPIL IL Service Service

Invoker Invoker

Consumer Consumer

TracingInterceptor Interceptor Tracing

Producer Producer

4. The Invoker and the interceptor chain

ServerSecurityInterceptor ServerSecurityInterceptor

1. Sending the message on the client side

JMSQueue JMSQueue

….. JMSDestination JMSDestination Manager Manager

JMSTopic JMSTopic

MDB MDB Container Container

JMSTopic JMSTopic

JVM JVMIL IL Service Service

8. Configuring the message softening

Remote Client VM Security Security Manager Manager 3. The Invocation Layers. - How do they work? - How to deploy them? - How to configure them? - How to secure them?

JBossMQ VM © JBoss, Inc. 2003-2005.

State State Manager Manager

JaasSecurityManager JaasSecurityManager 5. Configuring the JBossMQ security

Message Message Cache Cache

Persistence Persistence Manager Manager

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The inflow of a message through JBossMQ Professional Open Source™ 2. The ConnectionFactory. - How does it get bound in JNDI?

ConnectionFactory ConnectionFactory

Unified Invocation Layer

Session Session

UIL2 UIL2 Service Service

Connection Connection

7. Deploying a destination 6. The DestinationManager

HTTP HTTPIL IL Service Service

Invoker Invoker

Consumer Consumer

TracingInterceptor Interceptor Tracing

Producer Producer

4. The Invoker and the interceptor chain

ServerSecurityInterceptor ServerSecurityInterceptor

1. Sending the message on the client side

JMSQueue JMSQueue

….. JMSDestination JMSDestination Manager Manager

JMSTopic JMSTopic

MDB MDB Container Container

JMSTopic JMSTopic

JVM JVMIL IL Service Service

8. Configuring the message softening

Remote Client VM Security Security Manager Manager 3. The Invocation Layers. - How do they work? - How to deploy them? - How to configure them? - How to secure them?

JBossMQ VM

State State Manager Manager

JaasSecurityManager JaasSecurityManager 5. Configuring the JBossMQ security

Message Message Cache Cache

Persistence Persistence Manager Manager 9. Configuring the persistence

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© JBoss, Inc. 2003-2005.

The inflow of a message through JBossMQ Professional Open Source™ 2. The ConnectionFactory. - How does it get bound in JNDI?

ConnectionFactory ConnectionFactory

Unified Invocation Layer

Session Session

Connection Connection

UIL2 UIL2 Service Service

7. Deploying a destination 6. The DestinationManager

HTTP HTTPIL IL Service Service

Invoker Invoker

Consumer Consumer

TracingInterceptor Interceptor Tracing

Producer Producer

4. The Invoker and the interceptor chain

ServerSecurityInterceptor ServerSecurityInterceptor

1. Sending the message on the client side

10. The MDB Container

JMSQueue JMSQueue

….. JMSDestination JMSDestination Manager Manager

JMSTopic JMSTopic

MDB MDB Container Container

JMSTopic JMSTopic

JVM JVMIL IL Service Service

8. Configuring the message softening

Remote Client VM Security Security Manager Manager 3. The Invocation Layers. - How do they work? - How to deploy them? - How to configure them? - How to secure them?

JBossMQ VM © JBoss, Inc. 2003-2005.

State State Manager Manager

JaasSecurityManager JaasSecurityManager 5. Configuring the JBossMQ security

Message Message Cache Cache

Persistence Persistence Manager Manager 9. Configuring the persistence

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The Client Side Professional Open Source™

To send/receive a message – Look-up the ConnectionFactory and the Destination. – Create a Connection, Session a MessageProducer and a MessageConsumer. – If you want to send messages, don’t forget to start() the Connection! import import javax.jms.*; javax.jms.*; public public static static void void main(String[] main(String[] args) args) throws throws Exception Exception {{ Context Context context context == new new InitialContext(); InitialContext(); ConnectionFactory ConnectionFactory connectionFactory connectionFactory == (ConnectionFactory)context.lookup("ConnectionFactory"); (ConnectionFactory)context.lookup("ConnectionFactory"); Destination Destination topic topic == (Destination)context.lookup(“topic/MyTopic”); (Destination)context.lookup(“topic/MyTopic”); Connection Connection connection connection == connectionFactory.createConnection(); connectionFactory.createConnection(); Session Session session session == connection.createSession(true, connection.createSession(true, Session.AUTO_ACKNOWLEDGE); Session.AUTO_ACKNOWLEDGE); MessageProducer MessageProducer producer producer == session.createProducer(topic); session.createProducer(topic); TextMessage textMessage = session.createTextMessage(“some TextMessage textMessage = session.createTextMessage(“some text”); text”); connection.start(); connection.start(); producer.send(textMessage); producer.send(textMessage); }}

connection.close(); connection.close();

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© JBoss, Inc. 2003-2005.

The ConnectionFactory Professional Open Source™

A ConnectionFactory – Is a JMS Administered Object. – Encapsulates a set of connection configuration parameters that has been defined by the JMS server administrator. – A client uses it to create a connection with a JMS provider.

In JBossMQ, the ConnectionFactories are bound in JNDI by the Invocation Layers, during deployment. – UIL2 binds "ConnectionFactory" and "XAConnectionFactory“. – HTTPIL binds "HTTPConnectionFactory" and "HTTPXAConnectionFactory“ – JVM IL binds "java:/ConnectionFactory" and "java:/XAConnectionFactory“.

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The Invocation Layers Professional Open Source™

An Invocation Layer is a service responsible for handling client-to-server and server-to-client communication over an arbitrary protocol. Is made up of two interfaces: – ServerIL • a serializable object implementing this interface is included in the ConnectionFactory. • The client's connection will use it to send requests that are handled by the ServerILService on the server. – ClientIL • a serializable object implementing this interface is created on the client and sent to the server. It allows the server to invoke back on the client's ClientILService (mainly to push messages to the client as they arrive).

Available implementations: – Unified Invocation Layer Version 2 (UIL2) – HTTPIL – JVMIL

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The Unified Invocation Layer Version 2 Professional Open Source™

UIL2 uses a single TCP socket over which multiplexes client-to-server and server-to-client messages. – Convenient when the client is protected by a firewall that denies inbound connections. – Asynchronously sends and receives messages at transport level, avoiding a blocking round-trip at socket level. – The recommended Invocation Layer for remote access.

Unified Invocation Layer UIL2 ServerSocket ServerSocket ManagerHandler ManagerHandler

UILServerIL UILServerIL Socket Socket Manager Manager

Connection Connection

UILClientILService UILClientILService

Remote Client VM

© JBoss, Inc. 2003-2005.

Socket Socket Manager Manager

JMSServerInvoker JMSServerInvoker

UILServerIL UILServerIL

JBoss VM

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UIL2 Deployment and Configuration Professional Open Source™

UIL2 is a JBoss service so it is deployed by placing a service deployment descriptor (uil2-service.xml) in deploy/jms. Remove it if you don't use it! encoding="UTF-8"?> <server> <server> <mbean <mbean code="org.jboss.mq.il.uil2.UILServerILService“ code="org.jboss.mq.il.uil2.UILServerILService“ name="jboss.mq:service=InvocationLayer,type=UIL2"> name="jboss.mq:service=InvocationLayer,type=UIL2"> --> <depends <depends optional-attribute-name="Invoker">jboss.mq:service=Invoker optional-attribute-name="Invoker">jboss.mq:service=Invoker --> ConnectionFactory name="ConnectionFactoryJNDIRef">ConnectionFactory --> XAConnectionFactory name="XAConnectionFactoryJNDIRef">XAConnectionFactory --> ${jboss.bind.address} name="BindAddress">${jboss.bind.address} (continued (continued …) …)

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© JBoss, Inc. 2003-2005.

UIL2 Deployment Descriptor Professional Open Source™

(… (… continued) continued) --> 8093 name="ServerBindPort">8093 --> 60000 name="PingPeriod">60000 --> true name="EnableTcpNoDelay">true --> --> 120000 name="ReadTimeout">120000 --> --> 2048 name="BufferSize">2048 --> --> --> 1000000 name="ChunkSize">1000000

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UIL2 Configuration (1) Professional Open Source™

ConnectionFactoryJNDIRef – The JNDI name used to bind the ConnectionFactory corresponding to this IL.

XAConnectionFactoryJNDIRef – The JNDI name used to bind the XAConnectionFactory corresponding to this IL.

BindAddress – The interface to bind to. – Useful for a multihomed machine.

ServerBindPort – The port UIL2 service will listen on.

PingPeriod – The interval, in milliseconds, after which the client sends a ping message to the server to validate the connection. – A zero value disables pinging.

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© JBoss, Inc. 2003-2005.

UIL2 Configuration (2) Professional Open Source™

EnableTcpNoDelay – If enabled, the socket sends a TCP/IP packet as soon as the request is flushed, without waiting to fill the buffer. – Improves the request response time.

ReadTimeout – The period, in milliseconds, passed as SoTimeout value to the UIL2 socket. This allows detection of dead sockets. – This value must be larger than the PingPeriod.

ServerSocketFactory – The javax.net.ServerSocketFactory class to be used to create the service's ServerSocket. – Typically used to secure the connection using SSL sockets.

ClientSocketFactory – The javax.net.ServerSocketFactory class to be used to create the client sockets. – Typically used to secure the connection using SSL sockets.

SecurityDomain – Specifies the JNDI name of the JBoss security domain to use with JBoss SSL aware socket factories.

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Securing the UIL2 (1) Professional Open Source™

1. Generate a private-public key pair, using keytool. >> keytool keytool -genkey -genkey -alias -alias jbossmq jbossmq -keyalg -keyalg RSA RSA -keystore -keystore jbossmq.keystore jbossmq.keystore -validity -validity 3650 3650

Copy the keystore file in the server’s ‘conf’ directory. 2. Configure a new "SSL" security domain, that uses the previously created keystore. Add a new MBean configuration to a new file ‘ssl-domainservice.xml’ and deploy that file in the ‘deploy’ directory. encoding="UTF-8"?> <server> <server> <mbean <mbean code="org.jboss.security.plugins.JaasSecurityDomain" code="org.jboss.security.plugins.JaasSecurityDomain" name="jboss.security:service=JaasSecurityDomain,domain=SSL"> name="jboss.security:service=JaasSecurityDomain,domain=SSL"> <arg <arg type="java.lang.String" type="java.lang.String" value="SSL"/> value="SSL"/> resource:jbossmq.keystore name="KeyStoreURL">resource:jbossmq.keystore jbossmq name="KeyStorePass">jbossmq

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© JBoss, Inc. 2003-2005.

Securing the UIL2 (2) Professional Open Source™

3. Modify the UIL2 deployment descriptor to enable the security domain and to use the SSL socket factories. encoding="UTF-8"?> <server> <server> <mbean <mbean code="org.jboss.mq.il.uil2.UILServerILService" code="org.jboss.mq.il.uil2.UILServerILService" name="jboss.mq:service=InvocationLayer,type=UIL2"> name="jboss.mq:service=InvocationLayer,type=UIL2"> …. …. --> org.jboss.security.ssl.ClientSocketFactory name="ClientSocketFactory">org.jboss.security.ssl.ClientSocketFactory org.jboss.security.ssl.DomainServerSocketFactory name="ServerSocketFactory">org.jboss.security.ssl.DomainServerSocketFactory --> java:/jaas/SSL name="SecurityDomain">java:/jaas/SSL

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Securing the UIL2 (3) Professional Open Source™

4. Create the truststore that will be used by the client. >> keytool keytool -export -export -alias -alias jbossmq jbossmq -keystore -keystore jbossmq.keystore jbossmq.keystore -rfc -rfc -file -file jbossmq.cer jbossmq.cer Enter Enter keystore keystore password: password: jbossmq jbossmq ... ... >> keytool keytool -import -import -alias -alias jbossmq jbossmq -file -file jbossmq.cer jbossmq.cer -keystore -keystore jbossmq.truststore jbossmq.truststore Enter Enter keystore keystore password: password: jbossmq jbossmq ... ...

5. Set the VM system properties in client and server -Djavax.net.ssl.trustStore=jbossmq.truststore -Djavax.net.ssl.trustStorePassword=jbossmq and copy ‘jbossmq.trustore’ in the local directory.

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© JBoss, Inc. 2003-2005.

The Invoker Professional Open Source™

HTTP HTTP IL IL Service Service

HTTP HTTP IL IL Service Service

© JBoss, Inc. 2003-2005.

JMSServerInvoker JMSServerInvoker

ServerSecurityInterceptor ServerSecurityInterceptor

HTTP HTTP IL IL Service Service

TracingInterceptor TracingInterceptor

JMSServerInvoker implements the Invoker interface. The invoker is the target of the Invocation Layer services. Has the responsibility to pass the request to the ‘nextInterceptor’ in the chain.

JMSDestination JMSDestination Manager Manager

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The Interceptor Chain Professional Open Source™

An implementation of the "Chain of Responsibility" pattern The default configuration currently contains three interceptors: – The TracingInterceptor – The SecurityInterceptor • Performs authentication and authorization of the requests. – The JMDDestinationManager (the main server) • Contains a map of JMSDestinations

You can implement your own JBossMQ interceptor – It must be a JBoss Service. – It must expose a “nextInterceptor” managed attribute. – It must implement the org.jboss.mq.server.JMSServerInterceptor or extend org.jboss.mq.server.JMSServerInterceptorSupport. – You can insert it in the interceptor chain by adding the service declaration to ‘jbossmq-service.xml’.

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© JBoss, Inc. 2003-2005.

The Security Interceptor Professional Open Source™

The Security Interceptor delegates authentication and authorization of the requests to the JBossMQ SecurityManager. The JBossMQ security infrastructure manages three types of security information: – Authentication information (username and passwords or other type of security credentials). Authentication is delegated to a JBossSX JaasSecurityManager. – Principal to Role mapping. Delegated to the JaasSecurityManager. – Permissions to Role mapping, relative to a destination. • Specifies what roles are required to read/write from/to destination and to create a durable subscription on a topic. • The permissions are declared in the destination's deployment descriptor.

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The Security Manager Professional Open Source™

The SecurityManager maintains a security configuration map – –

Destination names are mapped to destination SecurityMetadata. The map is updated with each deployment/undeployment of a destination.

The SecurityManager delegates the authentication of a request to JaasSecurityManager instance –

Specify the JNDI name of the JaasSecurityManager as the value of the SecurityManager’s "SecurityDomain“ attribute.

The SecurityManager MBean is configured in the ‘jbossmq-service.xml’ deployment descriptor. …. …. <mbean <mbean code="org.jboss.mq.security.SecurityManager" code="org.jboss.mq.security.SecurityManager" name="jboss.mq:service=SecurityManager"> name="jboss.mq:service=SecurityManager"> name="DefaultSecurityConfig"> <security> create="true"/> java:/jaas/jbossmq name="SecurityDomain">java:/jaas/jbossmq <depends <depends optional-attribute-name="NextInterceptor">jboss.mq:service=DestinationManager optional-attribute-name="NextInterceptor">jboss.mq:service=DestinationManager …. ….

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© JBoss, Inc. 2003-2005.

Authentication (1) Professional Open Source™

The JaasSecurityManager’s LoginModule stack is configured in ‘login-config.xml’:

…. …. "jbossmq"> "required"> <module-option <module-option name name == "unauthenticatedIdentity">guest "unauthenticatedIdentity">guest <module-option <module-option name name == "dsJndiName">java:/DefaultDS "dsJndiName">java:/DefaultDS <module-option name = "principalsQuery"> <module-option name = "principalsQuery"> SELECT SELECT PASSWD PASSWD FROM FROM JMS_USERS JMS_USERS WHERE WHERE USERID=? USERID=? <module-option <module-option name name == "rolesQuery"> "rolesQuery"> SELECT ROLEID, 'Roles' FROM JMS_ROLES WHERE SELECT ROLEID, 'Roles' FROM JMS_ROLES WHERE USERID=? USERID=? …. ….

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Authentication (2) Professional Open Source™

If using a DynamicStateManager, the credentials are stored in ‘conf/jbossmqstate.xml’, and the JaasSecurityManager delegates to the StateManager: …. …. "jbossmq"> "required"> <module-option <module-option name name == "unauthenticatedIdentity">guest "unauthenticatedIdentity">guest <module-option <module-option name name == "sm.objectname">jboss.mq:service=StateManager "sm.objectname">jboss.mq:service=StateManager …. ….

The SecurityManager maintains an authentication cache, which maps session IDs to SubjectInfo instances. Once authenticated, the user’s SubjectInfo is added to the authenticated cache.

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Authorization Professional Open Source™

The SecurityManager authorizes the requests – add a message to a destination. – create/delete durable subscriptions on a topic.

It maintains a security metadata map. – Security meta data is added to the map every time a Queue or Topic is deployed. – Can be configured using the ‘SecurityConf’ attribute of the Destination's deployment descriptor. – The typical destination deployment descriptor is ‘deploy/jms/jbossmq-destinationsservice.xml’. – Security meta data consists in roles (not user names) and permissions. …. …. <mbean <mbean code="org.jboss.mq.server.jmx.Queue" code="org.jboss.mq.server.jmx.Queue" name="jboss.mq.destination:service=Queue,name=testQueue"> name="jboss.mq.destination:service=Queue,name=testQueue"> .... .... name="SecurityConf"> <security> <security> write="true"/> create="false"/> …. ….

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The Destination Manager Professional Open Source™

The JMSDestinationManager is the main broker for requests

TracingInterceptor Interceptor Tracing

ServerSecurityInterceptor ServerSecurityInterceptor

– Maintains a map of destinations and forwards inbound messages to their destinations. – Maintains a map of client consumers and outbound messages to their ClientConsumers. – Maintains a reference to the StateManager and delegates durable subscription related requests to the StateManager. – Maintains a reference to the MessageCache. – Maintains a reference to the PersistenceManager.

State State Manager Manager

destinations

JMSQueue JMSQueue

….. JMSTopic JMSTopic JMSDestination JMSDestination Manager Manager

Message Message Cache Cache

JMSTopic JMSTopic

Persistence Persistence Manager Manager

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Destinations Professional Open Source™

Queues are implemented as JMSQueues, which delegate to PersistentQueues. – SelectorPersistentQueue is an optimization of PersistentQueue for topic subscriptions that have selectors.

Topics are implemented as JMSTopic. – Non-durable subscriptions are implemented as a set of ExclusiveQueues. – Durable subscriptions are implemented as a set of PersistentQueues.

Destinations are deployed as regular JBoss Services, using a JBoss service deployment descriptor. The predefined destination definitions are available in ‘deploy/jms/jbossmq-destinations-service.xml’ Destinations can be created or destroyed at runtime using ‘jboss.mq:service=DestinationManager’'s managed operations: – createQueue()/destroyQueue() – createTopic()/destroyTopic()

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A Destination Deployment Descriptor Professional Open Source™

A Destination is a regular JBoss MBean, and it is deployed as such: encoding="UTF-8"?> <server> <server> <mbean <mbean code="org.jboss.mq.server.jmx.Topic" code="org.jboss.mq.server.jmx.Topic" name="jboss.mq.destination:service=Topic,name=testTopic"> name="jboss.mq.destination:service=Topic,name=testTopic"> <depends <depends optional-attribute-name="DestinationManager">jboss.mq:service=DestinationManager optional-attribute-name="DestinationManager">jboss.mq:service=DestinationManager <depends <depends optional-attribute-name="SecurityManager">jboss.mq:service=SecurityManager optional-attribute-name="SecurityManager">jboss.mq:service=SecurityManager name="SecurityConf"> <security> <security> write="true"/> create="false"/> create="true"/> <mbean <mbean code="org.jboss.mq.server.jmx.Queue" code="org.jboss.mq.server.jmx.Queue" name="jboss.mq.destination:service=Queue,name=testQueue"> name="jboss.mq.destination:service=Queue,name=testQueue"> <depends <depends optional-attribute-name="DestinationManager">jboss.mq:service=DestinationManager optional-attribute-name="DestinationManager">jboss.mq:service=DestinationManager <depends optional-attribute-name="SecurityManager">jboss.mq:service=SecurityManager <depends optional-attribute-name="SecurityManager">jboss.mq:service=SecurityManager name="SecurityConf"> <security> <security> write="true"/> create="false"/>

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Message Caching Professional Open Source™

Each message sent to a destination is first cached: – The JMS spec does not require NON_PERSISTENT messages to be stored. – However, if the messages are large and there are not enough queue receivers or there are many durable subscribes, storing the messages in memory could lead to an OutOfMemoryError. – MessageCache is the solution for this behavior. – Immediately after a Destination receives a message, caches it and it gets a MessageReference. – Instead of holding direct references to the messages the Destinations holds a MessageReference. – The MessageReference either holds a direct reference to the message or a pointer to the message in an offline store. – This allows the server to move messages in and out of memory. – Messages are saved to disk when memory starts to become full, using a LRU mechanism.

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Message Softening Professional Open Source™

The MessageCache softens the messages that have been transferred to external storage. – When the JVM's heap size passes the HighMemoryMark and starts to approach the MaxMemoryMark, the MessageCache begins softening messages. – Converts hard referenced messages to SoftReferences in memory. – Writes a persistent copy of the message to the CacheStore. – Messages are softened using a least recently used algorithm. – Typical settings for HighMemoryMark/MaxMemoryMark should be 80% and 90% of the -Xmx setting. You need to leave room (10% of memory if you set 90% for the max setting) to make sure there is spare memory to cope with any large messages you send. <mbean <mbean code="org.jboss.mq.server.MessageCache" code="org.jboss.mq.server.MessageCache" name="jboss.mq:service=MessageCache"> name="jboss.mq:service=MessageCache"> 50 name="HighMemoryMark">50 60 name="MaxMemoryMark">60 jboss.mq:service=PersistenceManager name="CacheStore">jboss.mq:service=PersistenceManager

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The Persistence Manager Professional Open Source™

If we want persistence, the JMS Messages must be explicitly made persistent:

sender.send(message, sender.send(message, DeliveryMode.PERSISTENT, DeliveryMode.PERSISTENT, priority, priority, 0); 0);

The PersistenceManager saves and restore PERSISTENT messages and those NON_PERSISTENT messages that have been softened (cache overflow). Works in cooperation with MessageCache – It maintains a transaction log for transactional sessions.

Available implementations: – JDBC Persistence Manager – File Persistence Manager – Null Persistence Manager - for the case you only deal with NON_PERSISTENT messages and you don't have access to a DataSource.

Note! the Null Persistence Manager doesn't offer you any protection from running out of memory, since it "persists" messages in ... memory.

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The JDBC Persistence Manager Professional Open Source™

Thg JDBC Persistence Manager is the recommended persistence manager – – – – –

JDBC2 and JDBC3 implementations available. Used for both persistent messages and on cache overflow. A production level database is recommended. Configured by default in ‘hsqldb-jdbc2-service.xml’. Typically the State Manager accesses the same persistence store, so if you change the Persistence Manager, you also have to change the State Manager configuration, available by default in ‘deploy/jms/hsqldb-jdbcstate-service.xml’

<mbean <mbean code="org.jboss.mq.pm.jdbc2.PersistenceManager“ code="org.jboss.mq.pm.jdbc2.PersistenceManager“ name="jboss.mq:service=PersistenceManager"> name="jboss.mq:service=PersistenceManager"> <depends <depends optional-attribute-name="ConnectionManager">jboss.jca:service=LocalTxCM,name=DefaultDS optional-attribute-name="ConnectionManager">jboss.jca:service=LocalTxCM,name=DefaultDS name="SqlProperties"> … …

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JDBC Persistence Manager’s SqlProperties Professional Open Source™

name="SqlProperties"> BLOB_TYPE=OBJECT_BLOB BLOB_TYPE=OBJECT_BLOB INSERT_TX INSERT_TX == INSERT INSERT INTO INTO JMS_TRANSACTIONS JMS_TRANSACTIONS (TXID) (TXID) values(?) values(?) INSERT_MESSAGE INSERT_MESSAGE == INSERT INSERT INTO INTO JMS_MESSAGES JMS_MESSAGES (MESSAGEID, (MESSAGEID, DESTINATION, DESTINATION, \\ MESSAGEBLOB, MESSAGEBLOB, TXID, TXID, TXOP) TXOP) VALUES(?,?,?,?,?) VALUES(?,?,?,?,?) SELECT_ALL_UNCOMMITED_TXS SELECT_ALL_UNCOMMITED_TXS == SELECT SELECT TXID TXID FROM FROM JMS_TRANSACTIONS JMS_TRANSACTIONS SELECT_MAX_TX SELECT_MAX_TX == SELECT SELECT MAX(TXID) MAX(TXID) FROM FROM JMS_MESSAGES JMS_MESSAGES SELECT_MESSAGES_IN_DEST SELECT_MESSAGES_IN_DEST == SELECT SELECT MESSAGEID, MESSAGEID, MESSAGEBLOB MESSAGEBLOB FROM FROM JMS_MESSAGES JMS_MESSAGES \\ WHERE WHERE DESTINATION=? DESTINATION=? SELECT_MESSAGE SELECT_MESSAGE == SELECT SELECT MESSAGEID, MESSAGEID, MESSAGEBLOB MESSAGEBLOB FROM FROM JMS_MESSAGES JMS_MESSAGES \\ WHERE WHERE MESSAGEID=? MESSAGEID=? AND AND DESTINATION=? DESTINATION=? MARK_MESSAGE MARK_MESSAGE == UPDATE UPDATE JMS_MESSAGES JMS_MESSAGES SET SET TXID=?, TXID=?, TXOP=? TXOP=? \\ WHERE MESSAGEID=? AND DESTINATION=? WHERE MESSAGEID=? AND DESTINATION=? UPDATE_MESSAGE UPDATE_MESSAGE == UPDATE UPDATE JMS_MESSAGES JMS_MESSAGES SET SET MESSAGEBLOB=? MESSAGEBLOB=? \\ WHERE WHERE MESSAGEID=? MESSAGEID=? AND AND DESTINATION=? DESTINATION=? UPDATE_MARKED_MESSAGES UPDATE_MARKED_MESSAGES == UPDATE UPDATE JMS_MESSAGES JMS_MESSAGES SET SET TXID=?, TXID=?, TXOP=? TXOP=? WHERE WHERE TXOP=? TXOP=? UPDATE_MARKED_MESSAGES_WITH_TX UPDATE_MARKED_MESSAGES_WITH_TX == UPDATE UPDATE JMS_MESSAGES JMS_MESSAGES SET SET TXID=?, TXID=?, TXOP=? TXOP=? \\ WHERE WHERE TXOP=? TXOP=? AND AND TXID=? TXID=? DELETE_MARKED_MESSAGES_WITH_TX DELETE_MARKED_MESSAGES_WITH_TX == DELETE DELETE FROM FROM JMS_MESSAGES JMS_MESSAGES WHERE WHERE TXOP=? TXOP=? AND AND \\ JMS_MESSAGES.TXID JMS_MESSAGES.TXID IN IN (SELECT (SELECT TXID TXID FROM FROM JMS_TRANSACTIONS) JMS_TRANSACTIONS) DELETE_TX DELETE_TX == DELETE DELETE FROM FROM JMS_TRANSACTIONS JMS_TRANSACTIONS WHERE WHERE TXID TXID == ?? DELETE_MARKED_MESSAGES DELETE_MARKED_MESSAGES == DELETE DELETE FROM FROM JMS_MESSAGES JMS_MESSAGES WHERE WHERE TXID=? TXID=? AND AND TXOP=? TXOP=? DELETE_TEMPORARY_MESSAGES DELETE_TEMPORARY_MESSAGES == DELETE DELETE FROM FROM JMS_MESSAGES JMS_MESSAGES WHERE WHERE TXOP='T' TXOP='T' DELETE_MESSAGE DELETE_MESSAGE == DELETE DELETE FROM FROM JMS_MESSAGES JMS_MESSAGES WHERE WHERE MESSAGEID=? MESSAGEID=? AND AND DESTINATION=? DESTINATION=? CREATE_MESSAGE_TABLE CREATE_MESSAGE_TABLE == CREATE CREATE CACHED CACHED TABLE TABLE JMS_MESSAGES JMS_MESSAGES (( MESSAGEID MESSAGEID INTEGER INTEGER NOT NOT NULL, NULL, \\ DESTINATION DESTINATION VARCHAR(255) VARCHAR(255) NOT NOT NULL, NULL, TXID TXID INTEGER, INTEGER, TXOP TXOP CHAR(1), CHAR(1), \\ MESSAGEBLOB MESSAGEBLOB OBJECT, OBJECT, PRIMARY PRIMARY KEY KEY (MESSAGEID, (MESSAGEID, DESTINATION) DESTINATION) )) CREATE_TX_TABLE CREATE_TX_TABLE == CREATE CREATE CACHED CACHED TABLE TABLE JMS_TRANSACTIONS JMS_TRANSACTIONS (( TXID TXID INTEGER, INTEGER, PRIMARY PRIMARY KEY KEY (TXID) (TXID) )) CREATE_TABLES_ON_STARTUP CREATE_TABLES_ON_STARTUP == TRUE TRUE

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The MDB Container Professional Open Source™

JBoss creates an MDB Container for each deployed MDB: – There is NO home and remote interface for an MDB. – The MDBs cannot be directly invoked, the MDB Container receives messages from a destination and forwards the messages to the beans. – Messages are delivered to the MDB container by a set of Sessions which are part of the ServeSessionPool. – The Sessions call into the JMSContainerInvoker and the JMSContainerInvoker detypes the invocation and passes it along the EJB container invocation chain. The MDB Container MessageDrivenContainer

StdServerSessionPool StdServerSession StdServerSession JVM Invocation Layer

SpyConnectionConsumer SpyXAConnection

Interceptors JMSContainerInvoker

StdServerSession StdServerSession

JVMClientIL JVMClientIL …..

…..

YourMDB

StdServerSession StdServerSession MessageListenerImpl

MessageDrivenInstancePool

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MDB Container Fine Tuning Professional Open Source™

Why multiple ServerSessions? – A JMS Session is a single-threaded context. Multiple Sessions allows us to send multiple simultaneous invocations into the MDB Container. – How to change the size of the ServerSessionPool? Change the configuration or define a new one in ‘conf/standardjbossxml’ message-driven-bean message-driven-bean default default <proxy-factory>org.jboss.ejb.plugins.jms.JMSContainerInvoker <proxy-factory>org.jboss.ejb.plugins.jms.JMSContainerInvoker <proxy-factory-config> <proxy-factory-config> …. …. <MinimumSize>1 <MinimumSize>1 <MaximumSize>15 <MaximumSize>15 … … <proxy-factory-config> <proxy-factory-config>

Other configuration/tuning options: – Configure the container interceptor chain. – Change the MDB instance pool size.

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High Availability JBossMQ Professional Open Source™

High Availability JBossMQ is implemented as a HASingleton Service – Only one running JBossMQ instance is available on a cluster. – If the JBossMQ master node fails, the JBossMQ instance fails-over to the first available node. Node Node 22 Node Node 33

Node Node 22

Node Node 33

JBossMQ JBossMQ

Singleton Fail-Over

Node Node 11 JBossMQ JBossMQ

Shared Database

Node Node 11 JBossMQ JBossMQ

Shared Database 51

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HA JBossMQ Features Professional Open Source™

High Availability JBossMQ Features: – Automatic server fail-over. – Transparent client connectivity to HAJMS, by looking up the ConnnectionFactories in HAJNDI. – Lossless recovery after fail-over for messages targeted to queues and topic durable subscribers *) – Client notification via connection’s ExceptionListener on fail-over.

* Shared production grade database recommended. There is NO inmemory replication of queued messages. The HA failover will work only for PERSISTENT messages!

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HA JBossMQ Deployment Professional Open Source™

HAJMS is deployed as part of the "all" configuration. Initially the JMS server is configured to persist data in a Hypersonic database instance. – Change this!!! If the master node fails, most likely the HSQL instance will fail so your persistent message date won't be available. – Normally you would be running a clustered application server against a more sophisticated database shared amongst all application server nodes.

All nodes in the cluster must be configured identically in regard to the JMS services and their persistent DataSource. Services to configure: – The Persistence Manager (described previously). The default configuration file is ‘server/all/deploy-hasingleton/jms/hsqldb-jdbc2-service.xml’. – The Sate Manager (described previously. The default configuration file is ‘server/all/deploy-hasingleton/jms/hsqldb-jdbc-state-service.xml’.

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Client-side fail-over detection Professional Open Source™

The failover must be explicitly initiated from the client code: – The error condition is detected installing an ExceptionListener. – The failover completes after a new ConnectionFactory is looked up in JNDI and a new Connection is created. … … private private void void connect(Context connect(Context context, context, String String topicName) topicName) throws throws Exception Exception {{ ConnectionFactory ConnectionFactory connectionFactory connectionFactory == (ConnectionFactory)context.lookup("ConnectionFactory"); (ConnectionFactory)context.lookup("ConnectionFactory"); connection connection == connectionFactory.createConnection(); connectionFactory.createConnection(); connection.setExceptionListener(new connection.setExceptionListener(new FailoverListener()); FailoverListener()); Session Session session session == connection.createSession(false, connection.createSession(false, Session.AUTO_ACKNOWLEDGE); Session.AUTO_ACKNOWLEDGE); .... .... connection.start(); connection.start(); }} (continued (continued …) …)

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Client-side fail-over detection Professional Open Source™

(… (… continued) continued) private private class class FailoverListener FailoverListener implements implements ExceptionListener ExceptionListener {{ private private static static final final int int RETRIES RETRIES == 5; 5; public public void void onException(JMSException onException(JMSException e) e) {{ int int retries retries == RETRIES; RETRIES; while(retries-while(retries-- >> 0) 0) {{

}}

}}

}}

try try {{ connection.close(); connection.close(); //// unregisters unregisters the the ExceptionListener ExceptionListener }} catch(Exception catch(Exception e2) e2) {{ //// II will will get get an an Exception Exception anyway, anyway, since since the the connection connection to to the the server server is is //// broken, broken, but but disconnect() disconnect() frees frees up up resouces resouces associated associated with with the the connection connection }} try try {{ connect(jndiContext, connect(jndiContext, TOPIC_NAME); TOPIC_NAME); break; break; }} catch(Exception catch(Exception e2) e2) {{ e.printStackTrace(); e.printStackTrace(); }}

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JBossMQ Anti-Patterns Professional Open Source™

What NOT to do with JBossMQ: – Contested queues with selectors that spend most of their time read/skipping messages that don't match the selector(s). – MDB singletons because you can't handle concurrent delivery. – Continually connecting/disconnecting to/from the server. – Not understanding the transaction context (client operations are with the queue/server, not with other clients).

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What is next? Professional Open Source™

While still one of the best open source JMS providers around, JBossMQ could be still further improved in regards of: – Performance – High Availability features.

A complete reimplementation it is currently under way – It will combine elements of a serverful and a serverless architecture. – It will take advantage of multicast capabilities of JGroups to increase the performance on LANs that support hardware multicast. – It will add transparent failover for JMS clients. – It will add in-memory message replication, so the HA failover will work for NON_PERSISTENT messages, too.

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