Chapter 3 Linux Installation

This chapter covers the following topics as they apply to a Linux installation of Message Queue 4.2:

• Hardware Requirements

• Upgrading from Previous Versions

• Installation Procedure

• Message Queue Packages (RPMs)

• Installed Directory Structure

• Uninstallation Procedure

Hardware Requirements

In order to install Message Queue 4.2, your Linux system should satisfy the minimum hardware requirements shown in Table 3–1. See Supported Platforms and Components for information on software requirements.

Upgrading from Previous Versions

Because Message Queue is installed with other products (such as Sun Java^TM System Application Server), you should check whether it has already been installed on your system. To do so, enter the command

   imqbrokerd  -version

If Message Queue is already installed, its version number will be displayed. The Message Queue 4.2 Installer will upgrade automatically to Version 4.2 from any Version 3.6 or later. If you have a version earlier than 3.6 installed, you will need to uninstall it before running the Message Queue 4.2 Installer.

The Message Queue 4.2 Installer does not share the same product registry with other installers, such as those of the Sun Java Enterprise System (JES) and Sun Java System Application Server, which include Message Queue as a component. The Message Queue Installer also installs or upgrades shared software components that Message Queue depends on, such as the Java Software Development Kit (SDK), Netscape Portable Runtime (NSPR), Network Security Services (NSS), and JavaHelp. Using this Installer to upgrade an earlier version of Message Queue that was installed with another installer may upgrade such shared components without correctly updating their version numbers in the other installer’s product registry, leaving that registry in an inconsistent state.

If you later run the other installer, the inconsistent registry entries may in turn cause that installer to inadvertently remove Message Queue 4.2. The safest and cleanest way to upgrade an earlier version of Message Queue that was installed with a different installer is as follows:

1. Use the other installer’s uninstaller to remove Message Queue.

2. Use the Message Queue 4.2 Installer to install Message Queue 4.2.

Installation Procedure

You can run the Message Queue Installer in any of three modes:

• In GUI (graphical user interface) mode, the Installer presents a series of graphical screens with which you interact using mouse clicks and keyboard text entry.

• In text mode, the Installer uses plain text displayed directly in your terminal window to simulate the appearance of the GUI screens. Instead of the mouse, you use keyboard keys such as Tab, Return, and arrow keys to interact with these screens. This is convenient for situations in which you do not have access to a windowing system to display the Installer’s full graphical user interface.

• In silent mode, the Installer operates from a predefined answer file representing your responses to the GUI screens. This allows you to script the installation process in advance and then perform it in batch mode without actually displaying the GUI (or text) screens and responding to them interactively.

The following sections describe each of these three modes of Installer operation.

Installing in GUI Mode

The following procedure shows how to use the Message Queue Installer in GUI mode to install the Message Queue 4.2 product on your Linux system.

To Install Message Queue in GUI Mode

1. Become the root user.

   You must have root user privileges to run the Message Queue Installer. Enter the command

      su
   

   and provide a valid root user password when prompted to do so.

2. Create a temporary directory.

   From your system’s command line, enter the command

      mkdir tempDir
   

   where tempDir is any name you choose for your temporary directory.

3. Download the Message Queue Installer to the temporary directory.

   The Installer is available for download from the Message Queue product Web site at

      http://www.sun.com/software/products/message_queue
   

   It is distributed as a compressed archive (.zip) file named

      mq4_1-installer-Linux_X86.zip
   

4. Go to the temporary directory.

   Enter the command

      cd tempDir
   

   where tempDir is the temporary directory to which you downloaded the Installer in step 3.

5. Decompress the Installer archive.

   Enter the command

      unzip mq4_1-installer-Linux_X86.zip
   

   This creates a subdirectory named

      mq4_1-installer
   

   containing the files needed for Message Queue 4.2 installation.

6. Switch to the Installer subdirectory.

   Enter the command

      cd mq4_1-installer
   

7. Start the Installer.

   Enter the command

      installer
   

   The Installer’s Welcome screen (Figure 3–1) appears.

   Figure 3–1 Installer Welcome Screen

   
   

8. Click the Next button.

   The Installer’s License screen (Figure 3–2) appears.

   Figure 3–2 Installer License Screen

   
   

9. Read and accept the product license agreement.

   Installation and use of the Message Queue product are subject to your acceptance of the license agreement. You must read and accept the terms of the license agreement before installing the product.

   1. Read the product license agreement.

   2. Make sure the radio button labeled “I accept the terms in the license agreement” is selected.

      If you instead select “I do not accept the terms in the license agreement,” the Next button becomes disabled. You cannot proceed with installation without accepting the license terms.

   3. Click the Next button.

      The Installer’s JDK Selection screen (Figure 3–3) appears.

      Figure 3–3 Installer JDK Selection Screen

      
      

10. Specify the version of the Java SDK for Message Queue to use.

    1. Select a Java SDK.

       You can do this in any of three ways:

       • Install the default SDK.

         Select the option labeled “Install and use the default version of the Java SDK.”

       • Choose an SDK already installed on your system.

         The drop-down menu under the option “Choose a Java SDK from the list below” lists existing SDKs found in standard locations on your system. You can use this option to specify one of these SDKs for Message Queue to use.

       • Provide an explicit path to an existing SDK.

         To use an SDK from a location other than the standard ones, enter its path in the text field under the option “Type in a Java SDK location below,” or use the button marked with an ellipsis (…) to browse to it interactively.

    2. Click the Next button.

       The Installer’s Multilingual Packages screen (Figure 3–4) appears.

       Figure 3–4 Installer Multilingual Packages Screen

       
       

11. Specify whether to install multilingual packages.

    By default, Message Queue is installed to operate in the English language only. The Multilingual Packages screen allows you to install it for use in another language.

    1. If you will be using Message Queue in a language other than English, select the checkbox labeled “Install Message Queue multilingual packages.”

       If you will be using Message Queue only in English, leave this checkbox deselected.

       ---

       Caution –

       If you choose not to install the multilingual packages and later decide that you do need them after all, there is no convenient way to install them incrementally: you will have to uninstall Message Queue and then repeat the entire installation procedure with the multilingual packages selected. Before proceeding to install without the multilingual packages, be sure you will not be needing them in the future.

       ---

    2. Click the Next button.

       The Installer’s Upgrade screen (Figure 3–5) appears.

       Figure 3–5 Installer Upgrade Screen

       
       

12. Specify whether to upgrade Message Queue and its shared components.

    If an earlier version of Message Queue exists on your system, or if any of the shared components on which Message Queue depends need to be upgraded from earlier versions, the Upgrade screen displays them in a scrollable list along with their current and required versions. If no upgrades are needed, the existing components are simply listed with their version numbers and a notation that they will remain at their current versions. In this case, the “Upgrade” and “Do not upgrade” radio buttons do not appear; just click Next to proceed to the next step.

    ---

    Caution –

    It is possible that upgrading Message Queue’s shared components may break other software components on your system that depend on the earlier versions previously installed. Be sure there are no such dependencies before proceeding with the upgrade.

    ---

    To proceed with the upgrade:

    1. Make sure the radio button labeled “Upgrade” is selected.

       If you instead select “Do not upgrade,” the Next button becomes disabled; your only options at this point are Back (to return to the previous screen) or Cancel (to exit the Installer without completing installation).

    2. Click the Next button.

       The Installer’s Ready screen (Figure 3–6) appears.

       Figure 3–6 Installer Ready Screen

       
       

13. Click Install to begin the installation.

    The Installer’s Progress screen (Figure 3–7) appears, tracking the progress of the installation as it proceeds.

    Figure 3–7 Installer Progress Screen

    
    

    When installation is complete, the Installer's Sun Connection Registration screen (Figure 3–8) appears.

    Figure 3–8 Sun Connection Registration Screen

    
    

14. Register Message Queue with Sun Connection.

    Sun Connection is a Sun-hosted service that helps you track, organize, and maintain Sun hardware and software. When you register a Message Queue installation with Sun Connection, information such as the release version, host name, operating system, installation date, and other such basic information is securely transmitted to the Sun Connection database. The Sun Connection inventory service can help you organize your Sun hardware and software, while the update service can inform you of the latest available security fixes, recommended updates, and feature enhancements.

    Registration requires that you have a Sun Online account or create one. If you do not already have an account, the installer provides the following screen (Figure 3–9) for creating a Sun Online account:

    Figure 3–9 Create Sun Online Account Screen

    
    

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    Note –

    If you choose not to register Message Queue during installation, you can subsequently register Message Queue by running the installer in register-only mode, as follows:

    # installer -r

    The register-only mode requires that Message Queue 4.2 already be installed and will display only the installer screens related to registration.

    ---

    When Sun Connection registration is complete, the Installer’s Summary screen (Figure 3–10) appears, summarizing the steps that were performed during installation.

    Figure 3–10 Installer Summary Screen

    
    

    You can click the links on this screen for a detailed summary report and a log file giving more details on the installation.

15. Click the Exit button to dismiss the Summary screen.

    Message Queue installation is now complete.

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    Tip –

    After installation is complete, you can check that the expected versions of Message Queue and the Java runtime have been installed by navigating to the Message Queue /bin directory and executing the command

       imqbrokerd  -version
    

    The output from this command identifies the versions of Message Queue and the Java SDK that are installed on your system.

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Installing in Text Mode

For situations in which you do not have access to a windowing system to display the Installer’s full graphical user interface, the Message Queue Installer provides an alternate text mode that simulates the operation of the GUI using plain text displayed directly in your terminal window. For example, Figure 3–11 shows the text-mode counterpart of the Welcome screen shown earlier in Figure 3–1. Instead of clicking the Next button with the mouse, you would use the Tab key to advance the cursor to that button, then select it by pressing Return.

Figure 3–11 Installer Welcome Screen in Text Mode

To start the Installer in text mode, use the -t option when invoking it from the command line:

   installer  -t

The rest of the installation process is essentially the same as described above under Installing in GUI Mode, except that instead of the mouse, you must use keyboard keys such as Tab, Return, and arrow keys to select the various elements of the Installer screens.

Installing in Silent Mode

In silent mode, the Installer operates from a predefined answer file representing your responses to the GUI screens. This allows you to script the installation process in advance and then perform it in batch mode without actually displaying the GUI screens and responding to them interactively.

To create an answer file, start the Installer with the -n option:

   installer  -n answerFile

where answerFile identifies the file in which to record your responses. This causes the Installer to execute a “dry run,” presenting the sequence of GUI screens without actually performing the installation. Your input responses are recorded in the specified answer file. You can then perform the installation at a later time by starting the Installer with the -s (“silent”) option, specifying the same answer file:

   installer  -s  -a answerFile

This performs a silent installation as defined by the answer file, without visibly displaying the GUI (or text) screens.

Manually Configuring the Java Runtime Environment

The Message Queue Installer’s JDK Selection screen is not the only way to specify a version of the Java Runtime Environment for Message Queue to use. The JRE used by the Message Queue command line utilities (imqadmin, imqbrokerd, imqcmd, imqobjmgr, imqdbmgr, imqusermgr, imqkeytool) is determined by the following sources, in order of precedence:

1. The -jrehome or -javahome command line option to the imqbrokerd command. (If both are specified, the one occurring last on the command line takes precedence).

2. The J2SE file location specified in the jdk.env file. (This file is deprecated, but is still supported for backward compatibility. For historical reasons, it has higher priority than anything else except option 1.)

3. The IMQ_JAVAHOME environment variable.

4. The environment variable IMQ_DEFAULT_JAVAHOME in the imqenv.conf file.

5. The system default locations, as specified in the documentation for your platform.

To check which version of the Java runtime Message Queue will use, enter the command

   imqbrokerd  -version

The output from this command includes the version and pathname of the configured JRE: for example,

   Java Runtime: 1.5.0_12 Sun Microsystems Inc. /usr/java/jdk1.5.0_12/jre

When you specify a JRE location through the Installer’s JDK Selection screen, the Installer saves that location as the value of IMQ_DEFAULT_JAVAHOME in the imqenv.conf file (option 4 in the list above). On Linux, this file is located at

   /etc/opt/sun/mq/imqenv.conf

After a successful Message Queue installation, it should include something like the following:

   IMQ_DEFAULT_JAVAHOME=/usr/java/jdk1.5.0_12

You can override this setting, however, either by editing the imqenv.conf file or by setting one of the other options higher in the list. This can be useful, for instance, for testing or reconfiguring the broker when a newer JRE version becomes available. Understanding how the JRE is determined can also help in troubleshooting problems. For instance, if the imqbrokerd -version command shows that Message Queue is using an unexpected JRE, it may be that one of the higher-precedence options has been set inadvertently (such as by an old jdk.env file that should have been deleted).

Configuring Message Queue for Automatic Startup

To configure the Message Queue message broker to start up automatically at boot time, become the root user and edit the configuration file /etc/opt/sun/mq/imqbrokerd.conf. Table 3–2 shows the startup properties you can set in this file.

YES
NO

YES
NO

To check that startup changes are correct without booting the system, you can, as the root user, explicitly run the Message Queue initialization script in debug mode with the command

   env DEBUG=1 /etc/init.d/imq  start

Message Queue Packages (RPMs)

Table 3–3 lists the packages (RPMs) used by Message Queue on the Linux platform.

Installed Directory Structure

Table 3–4 shows the installed directory structure for a full (all RPMs) installation of Message Queue 4.2 on the Linux platform.

The directory structure may vary if you have installed Message Queue as part of a Sun Java System Application Server installation.

Uninstallation Procedure

Like the Installer, the Message Queue Uninstaller can be run in any of three modes of operation:

• In GUI (graphical user interface) mode, the Uninstaller presents a series of graphical screens with which you interact using mouse clicks and keyboard text entry.

• In text mode, the Uninstaller uses plain text displayed directly in your terminal window to simulate the appearance of the GUI screens. Instead of the mouse, you use keyboard keys such as Tab, Return, and arrow keys to interact with these screens. This is convenient for situations in which you do not have access to a windowing system to display the Uninstaller’s full graphical user interface.

• In silent mode, the Uninstaller operates from a predefined answer file representing your responses to the GUI screens. This allows you to script the uninstallation process in advance and then perform it in batch mode without actually displaying the GUI (or text) screens and responding to them interactively.

The following sections describe each of these three modes of Uninstaller operation.

The Message Queue installation includes several scripts and executables named uninstaller, both in the Installer .zip bundle and on your system after installation. To uninstall Message Queue 4.2, it is important that you run the correct uninstaller executable, located at

   /var/opt/sun/install/contents/mq/uninstaller

Be careful not to invoke some other uninstaller by mistake.

Uninstalling in GUI Mode

The following procedure shows how to use the Message Queue Uninstaller in GUI mode to uninstall Message Queue 4.2 from your Linux system.

To Uninstall Message Queue in GUI Mode

1. Set your working directory to the directory containing the Uninstaller.

   From your system’s command line, enter the command

      cd /var/opt/sun/install/contents/mq
   

2. Become the root user.

   You must have root user privileges to run the Message Queue Uninstaller. Enter the command

      su
   

   and provide a valid root user password when prompted to do so.

3. Start the Uninstaller.

   Enter the command

      uninstaller
   

   The Uninstaller’s Ready screen (Figure 3–12) appears.

   Figure 3–12 Uninstaller Ready Screen

   
   

4. Click the Remove button.

   The Uninstaller’s Progress screen (Figure 3–13) appears.

   Figure 3–13 Uninstaller Progress Screen

   
   

   When uninstallation is complete, the Uninstaller’s Summary screen (Figure 3–14) appears, summarizing the steps that were performed during uninstallation. You can click the links on this screen for a detailed summary report and a log file giving more details on the uninstallation.

   Figure 3–14 Uninstaller Summary Screen

   
   

5. Click the Exit button to dismiss the Summary screen.

   Message Queue uninstallation is now complete.

Uninstalling in Text Mode

For situations in which you do not have access to a windowing system to display the Uninstaller’s full graphical user interface, the Message Queue Uninstaller provides an alternate text mode that simulates the operation of the GUI using plain text displayed directly in your terminal window. For example, Figure 3–15 shows the text-mode counterpart of the Ready screen shown earlier in Figure 3–12. Instead of clicking the Next button with the mouse, you would use the Tab key to advance the cursor to that button, then select it by pressing Return.

Figure 3–15 Uninstaller Ready Screen in Text Mode

To start the Uninstaller in text mode, use the -t option when invoking it from the command line:

   uninstaller  -t

The rest of the uninstallation process is essentially the same as described above under To Uninstall Message Queue in GUI Mode, except that instead of the mouse, you must use keyboard keys such as Tab, Return, and arrow keys to select the various elements of the Uninstaller screens.

Uninstalling in Silent Mode

In silent mode, the Uninstaller operates from a predefined answer file representing your responses to the GUI screens. This allows you to script the uninstallation process in advance and then perform it in batch mode without actually displaying the GUI screens and responding to them interactively. To create an answer file, start the Uninstaller with the -n option:

   uninstaller  -n answerFile

where answerFile identifies the file in which to record your responses. This causes the Uninstaller to execute a “dry run,” presenting the sequence of GUI screens without actually performing the uninstallation. Your input responses are recorded in the specified answer file. You can then perform the uninstallation at a later time by starting the Uninstaller with the -s (“silent”) option, specifying the same answer file:

   uninstaller  -s  -a answerFile

This performs a silent uninstallation as defined by the answer file, without visibly displaying the GUI (or text) screens.