The following figure shows the location of files that are needed to set and manage JEUS and JEUS MQ servers. "JEUS_HOME" is the JEUS installation directory path.

Click [Servers] on the left pane to go to the Servers list page. Click on the name of the server to be set in the server list to go to the server configuration screen. It is recommended to use WebAdmin to configure JEUS MQ servers.

In JEUS WebAdmin, the JEUS MQ server configuration includes the following menus.

The following describes each JMS configuration screen. Since the [Basic] menu does not contain JMS related settings, its description is omitted.

[Resource]

On the JMS Resources page, you can configure JMS resources. Go to [Servers] > [Server Name] > [Resources] tab, and select the [JMS Resources] menu.

The following is the JMS Resources page. For more information, refer to "3.2. Configuring JMS Resources".

[Engine]

On the JMS Engine page, you can configure JEUS MQ servers. Go to [Servers] > [Server Name] > [Engine] tab, and select the [JMS Engine] menu.

The JMS Engine screen contains the following menus.

Like Queues or Topics, JEUS MQ servers register destinations in JEUS JNDI Service by reading the domain configuration.

In the Destination section of the JMS Resources page, select a resource from the list to go to the resource configuration page. Enter the Destination settings, and then click [OK]. To reset the settings, click [Reset].

Destination Memory Management

If messages fail to be sent to a client and accumulate at the destination, an OutOfMemoryError may occur on the JVM and the server may be terminated. To avoid this problem, JEUS MQ applies different memory management policies for each destination.

JEUS MQ servers hold strong references to message contents when the destination does not use a lot of memory. JEUS MQ servers operate according to the 'Quota' property settings.

Even after a message at a destination is deleted from the memory, the message will not be lost. Since the message is saved in the storage, a JEUS MQ server can read and process the message in the storage when necessary. The processing speed is slower when using the storage than memory.

Controlling Message Flow

The "Max Pending Limit" and "Resume Dispatch Factor'" properties in the destination screen are used to control the message flow. If the message listener is registered in a queue or topic, and when messages arrive, the messages will be immediately sent to the consumers. If the client cannot process the messages fast enough, the messages are accumulated on the client and an OutOfMemory error occurs. To prevent this error, you need to specify the maximum number of messages that can accumulate on the client after which the server suspends sending messages for a given time.

Messages arriving in the queue are stored in the server until the client calls to receive them, but Topic is only delivered to clients that exist at the moment the message arrives. In this case, if you want to keep the message until the client receives it while using the Topic, use the durable subscriber. Thus, you can only set the durable subscriber to the Topic type destination.

Since durable subscribers are created by clients, if the message that is sent to the topic arrives before the durable subscriber is created, it does not get delivered to the client. To resolve this problem, JEUS MQ registers a durable subscriber before the server starts so that it can send a message when a client is connected. Similar to invoking the Session.createDurableSubscriber() method, the client ID, subscription name, and topic must be specified when configuring a durable subscriber using JEUS WebAdmin. A message selector can also be configured.

In the Durable Subscriber section of the JMS Resource page, select a resource from the list to go to the resource configuration screen. Enter the Durable Subscriber settings and then click [OK]. To reset the settings, click [Reset].

Click [Basic] on the JMS Engine page. The basic JMS engine information page appears.

This page lists the failover settings and advanced JMS engine options. If you want to enable recovery from a server or network failure, you can configure the failover settings. For more information about the failover settings, refer to "Chapter 5. JEUS MQ Failover".

Advanced Options

In the Advanced Options section of the JMS engine page, you can configure the thread pool information.

There are two main types of message handling in the JMS engine. First, a generic message is processed as a single thread by the event manager in order to avoid contention and concurrency. Other special functions, message transfer between cluster, transaction control, and JMS engine control are handled by a thread pool according to each type.

The following is the Advanced Options section.

A JEUS MQ server communicates with a client through a service channel. Each JEUS MQ server must have one service channel, and it is possible to set a different network such as a service URL for each service channel. To set a listener that the service channel uses, go to [Servers] > [Resource] > [Listener]. For more information about listeners, refer to JEUS Server Guide. "2.3.3. Listener Configuration".

Go to [Servers] > [Server Name] > [Engine] > [JMS Engine] > [Service Config] to see the list of listeners for the service channel. When a listener is selected from the list, the following configuration screen appears. Enter the Service Config settings, and then click [OK]. To reset the settings, click [Reset].

A connection factory is a JMS management object that contains the connection information needed to access the JMS server and basic information for the client. It is created when the JEUS MQ server boots, and registered in the JEUS JNDI service.

Go to [Servers] > [Server Name] > [Engine] > [JMS Engine] > [Connection Factory] to see the list of connection factories. When a connection factory is selected from the list, the following configuration page appears. Enter the Connection Factory settings, and then click [OK]. To reset the settings, click [Reset].

A persistence store is needed to restore messages, subscriptions, or transactions to the previous state when the server restarts. If a persistence store is not configured, a message that the client sent in the DeliveryMode.PERSISTENT mode cannot be properly delivered if the server fails. JEUS MQ provides two types of persistence stores, journal log and database.

To configure a persistence store, go to [Servers] > [Engine] > [JMS Engine] > [Persistence Store]in WebAdmin.

Select Journal to use the logging method or select Jdbc to use the database method for the persistent store.

For more information about message sorting, refer to "6.2. JEUS MQ Message Sort".

The following describes how to manage servers using jeusadmin and WebAdmin.

Using WebAdmin

You can manage the connection factories, destinations, and durable subscribers that are required for JMS in WebAdmin. The resources can be added or deleted using [Add] or [Delete].

Using the Console Tool

You can manage the server resources by executing various commands in the console tool. The console tool is found in the following directory.

JEUS_HOME/bin/

The following are the jmsadmin commands.

Servers can be monitored using jmsadmin and WebAdmin.

Using WebAdmin

Go to [Monitoring] > [JMS] to monitor the current status of JEUS MQ servers.

Using the Console Tool

Server resources can be checked by executing various commands in the console tool. The console tool is in the following directory.

JEUS_HOME/bin/

The following commands are provided for server monitoring.