DB2 Version 7.1 for Linux HOWTO

Dan Scott

Revision History
Revision 1.2.62002-09-21Revised by: dbs
Add Mandrake 8.1, SuSE 7.3 install instructions from contributor Mykola Buryak.
Revision 1.2.52002-07-16Revised by: dbs
Fixed or removed some broken links, added a few new resources.
Revision 1.2.42001-06-02Revised by: dbs
Running JDK 1.1.8 on Red Hat 7.1
Revision 1.2.32001-04-25Revised by: dbs
Red Hat 7.1 install instructions, more DB2 on Debian info, connecting to AS/400 databases, buffer pool memory limits, converted to DocBook XML.
Revision 1.2.12000-10-25Revised by: dbs
Basic Red Hat 7.0 info, additional Debian instructions.
Revision 1.22000-09-25Revised by: dbs
IBM JDK 1.3 works! More troubleshooting.
Revision 1.12000-07-28Revised by: dbs
Documented _SHM_ID_BITS kernel parameter tuning for increasing number of available connections. Added basic indexing.
Revision 1.02000-07-06Revised by: dbs
Added basic Debian instructions. Corrected some factual, stylistic, and grammatical mistakes. Licensed document under GNU GPL. Submitted document to LDP.
Revision 0.72000-04-26Revised by: dbs
Based on DB2 V7.1 beta release, wrote install instructions for Caldera 2.4, Red Hat 6.2, SuSE 6.2, SuSE 6.3, and TurboLinux 6.0.

Table of Contents
1. Introduction
1.1. Why a DB2 installation HOWTO?
1.2. Who should read this HOWTO?
1.3. New versions of this document
1.4. Copyright and License
1.5. Credits
1.6. About the author
2. Prerequisites
2.1. What are prerequisites?
3. Preparing your distribution for DB2
3.1. Caldera OpenLinux 2.4
3.2. Mandrake Linux 7.2
3.3. Mandrake Linux 8.1
3.4. Red Hat Linux 6.2
3.5. Red Hat Linux 7.1
3.6. SuSE Linux
3.7. TurboLinux 6.0
4. Installing DB2 using db2setup
4.1. Using the db2setup utility
4.2. Installing DB2 components
5. Installing DB2 on other Linux distributions
6. Creating DB2 instances
6.1. Overview of DB2 Administration Server
6.2. Overview of DB2 instance
7. Removing DB2
8. Using DB2
8.1. DB2 Control Center
8.2. DB2 Information Center
8.3. The DB2 command line
9. Troubleshooting
9.1. Problems with DB2 installation
9.2. Problems creating a DB2 instance
9.3. Problems using DB2
9.4. Problems starting the DB2 Control Center
10. Improving DB2 Version 7.1 performance on Linux
10.1. Increasing maximum connections
10.2. Creating and configuring buffer pools
11. Installing the IBM Developer Kit for Java
12. Using the 2.4 kernel with DB2 Version 7.1
A. Resources
B. GNU General Public License
B.1. Preamble

1. Introduction

1.1. Why a DB2 installation HOWTO?

Ever since DB2 Version 5.2 was ported to Linux in 1998 and made available as a beta download, there has been a lot of interest in DB2 on Linux. The beta represented one of IBM's first dips into the waters of Linux, and it generated a lot of feedback. In fact, if you read through the newsgroups, you still see occasional questions from people who are trying out the Version 5.2 beta. (I don't know where they're getting it, but they're out there.) And, not surprisingly, they run into problems. It was a beta product, after all.

Anyway, I've been trying out DB2 on Linux since Version 5.2, so I've had a chance to witness the improvements over the past couple of years. I've also made a lot of use of the Linux Documentation Project in that time, and wanted to contribute something to the LDP. So I decided to write about the one thing that I really know something about on Linux, and hope that it helps someone else out there.

DB2 on Linux has come a long way since Version 5.2. The first supported release of DB2 on Linux was Version 6.1 in 1999, which removed many of the installation hurdles faced by the Version 5.2 beta testers.

DB2 Version 7.1 is the second major release that supports Linux, and since it's a new release I'm expecting that a new wave of people curious about DB2, as well as people migrating from Version 6.1, are going to try installing this new release on Linux. To that end, I'm writing this HOWTO to share my experiences and help smooth your installation. One of the big boosts comes from the standardization on the IBM Developer Kit for Java, which improves the stability of the DB2 Control Center and enables application developers to write stored procedures and UDFs in Java. DB2 Version 7.1 also introduces the ability to write stored procedures in SQL.

As time permits, I hope to provide hints and tips for improving the performance of DB2 on Linux, and for configuring the environment on various Linux distributions to be able to build DB2 applications in C, C++, and Java.


1.2. Who should read this HOWTO?

If you plan to install DB2 Version 7.1 on one of the Linux distributions supported by IBM, this document is for you. The distributions that IBM officially supports are:

For Debian and Slackware, I have included very basic installation instructions or links to other resources in Section 5. If you have any other installation success stories, please forward me the details and I'll try to expand the section. As time permits, I plan to try to duplicate and confirm these installation instructions.

If you install DB2 Version 6.1 for Linux and DB2 hangs on the db2start command, see db2start hangs on Linux distributions built with glibc 2.1. I don't include any other DB2 Version 6.1 information in this document. If you plan to install DB2 Version 5.2 on Linux, don't! (Have I emphasized that point enough? All right, I'll stop now.) The Personal Developer's Edition of DB2 Version 7.1 is available as a free (beer) download from IBM, at the DB2 Universal Database download site. Registration is required, and, of course, your copy of DB2 is only free as long as you don't use it in a production environment.

This document is really meant to help you install DB2 Version 7.1 on the previously listed Linux distributions. I've installed DB2 on all of the distributions supported by IBM and noted the prerequisites and quirks for each of them. I don't go into detail about the various features of DB2, or what each installation option means, but I do cover the basics that you need to know to get it installed.


1.5. Credits

Dan Scott is the originator and current maintainer of this HOWTO. Please send all suggestions for improvement, criticisms, or more-or-less related questions to me at (remove REM in my email address before sending). Please send all spam or hate mail to /dev/null.

Feedback and suggestions for improvement have been provided by Susan Williams, Serge Boivin, Darin McBride, and Xiaoyan Zhao. Ronnie Seagren did an awesome job of editing the original version for style and consistency.

Additional thanks to:

  • Andika Triwidada for contributing instructions to install DB2 V7.1 on Debian using the rpm utility.

  • Michael Naughton for braving Red Hat 7 and figuring out the libncurses.so.4 prerequisite.

  • Christoph Shmitz for resolving license problems with DB2 installed via alien.

  • Claus Fischer for solving a DB2 on Debian problem with updating instances and contributing cataloging instructions for DB2 on AS/400.

  • Mykola Buryak for contributing the sections on Mandrake Linux 8.1 and SuSE 7.3.


2. Prerequisites

2.1. What are prerequisites?

Prerequisites are what you, your machine, and your distribution require before you will be able to successfully install or use DB2. The required prerequisites come straight from IBM DB2 Universal Database for UNIX Quick Beginnings. The suggested prerequisites come from experience. For your convenience, I've divided them into hardware and software requirements.

Hardware prerequisites

Processor

x86 compatible (for example, Intel, AMD, or Cyrix). I've successfully installed DB2 Version 7.1 on a Pentium Pro 200 and a Pentium II 350. Your experiences with other x86 processors would be appreciated.

Memory

For application development, I've found 96 MB of RAM is enough to run a small database and test out your applications. Even the Control Center responds acceptably if your processor speed is fast enough. In my case, I was working with a Thinkpad 600 equipped with a Pentium 233 MMX processor and 96 MB of RAM. However, more memory is recommended if you're putting your database into production or running multiple services.

Free disk space

Of course, this depends on the components you install, but for a typical installation of the DB2 Version 7.1 server, the Administration Client, the Application Development Client, the documentation, and the creation of a sample database, you will need about 350 MB of free disk space.

Software prerequisites

glibc

2.1.2 or greater. This can be a tough part of Linux to upgrade on its own, so if your current distribution doesn't meet this requirement, I would strongly suggest upgrading your entire distribution. For example, I tried upgrading only the glibc portion of TurboLinux 4.0 from 2.1.1 to 2.1.3 and ran into a whole world of trouble.

DB2 Version 7.1 should work with glibc 2.1.1. IBM sets prerequisites based on the systems with which they tested.

kernel

2.2.12 or greater. I've upgraded to both 2.2.19 and 2.4.3 and recompiled the kernel for my own purposes, and DB2 seems to work as well as before.

DB2 Version 7.1 should work with a minimum of kernel 2.2.10. IBM sets prerequisites based on the systems with which they tested.

libncurses

4.x. For db2setup to work correctly, this version of the library must be available on your system with the following pathname: /usr/lib/libncurses.so.4.

libstdc++-libc6.1-1.so.2

A file or symbolic link by this exact name is mandatory. On most distributions, this is a symbolic link to libstdc++-2.9.0.so, but on several recent distributions this is a symbolic link to libstdc++-2.10.0.so.

Note

In previous versions of this HOWTO, I stated that the exact version of libstdc++-2.9.0.so was mandatory. I was wrong.

pdksh

5.2 or greater. This is a public domain version of the Korn shell that both the DB2 installer and the DB2 commands require. You cannot do anything with DB2 without installing pdksh.

rpm

3.0 or greater. DB2 for Linux is distributed as a number of RPM packages, so you won't get far without this piece of software. For information on installing DB2 on distributions without using RPM, see Section 5.

Java

The IBM Developer Kit for Java, 1.1.8 or 1.3, is an optional component, but is required to:

  • use the DB2 Control Center to administer your databases using a graphical user interface

  • create or run Java applications, including stored procedures and user-defined functions

As of this writing, the minimum required level of the IBM Developer Kit for Java 1.1.8 is the March 22, 2000 release. You can get the IBM Developer Kit and Runtime Environment for Linux, Java Technology Edition, from the IBM Java Developer Kit downloads web site as follows:

Please note: Other versions of Java, such as the Blackdown or Sun JDKs, have not been tested with DB2 and are not supported by IBM. And no, none of the distributions I have seen so far package the IBM JDK. But do yourself a favour, and get the IBM Developer Kit for Java.

Web browser

DB2 calls the netscape command when you:

  • display the online help for the DB2 Control Center

  • display information using the DB2 Information Center

The easiest approach is to install Netscape Navigator or Communicator on your system. Netscape version 4.72 or above is required to display the Business Intelligence Quick Tour, because of its extreme use of JavaScript.

To use a browser other than Netscape to display online help or information, create a link called netscape to your preferred browser executable. The link must appear in your PATH. For example, to display online help with mozilla, you could create a link in /usr/local/bin with the following command:
bash# ln -s /usr/bin/mozilla-bin /usr/local/bin/netscape

In the following table:

  • unknown indicates that I don't know what the default level is, and I haven't installed DB2 on this distribution (your feedback is welcome!)

  • okay indicates that I don't know what the default level is, but it worked when I installed DB2

  • ** as a prefix indicates that the default level is not acceptable and must be replaced or supplemented with a compatible library


3. Preparing your distribution for DB2

3.1. Caldera OpenLinux 2.4

3.1.1. Before installing DB2 on Caldera OpenLinux

This section contains instructions that you must follow before installing DB2.

Preparing for the installation of DB2

  1. Install the pdksh-5.2.14-1.i386.rpm package from the Caldera OpenLinux CD-ROM in the /Packages/RPMS/ directory. For example, log in as root, mount the CD-ROM, and enter the following command to install the pdksh package:
    bash# rpm -ivh /mnt/cdrom/Packages/RPMS/pdksh-5.2.14-1.i386.rpm

  2. Remove the jdk package, (JDK 1.2.2 from Sun), since it will conflict with the IBM Developer Kit for Java that you will install in the next step. To remove Sun's JDK, issue the following command as root:
    bash# rpm -e jdk

  3. Install the IBM Developer Kit for Java. A brief set of installation directions is included in Section 11.

  4. Edit the JAVA_HOME and PATH entries in /etc/config.d/shells/bashrc to remove the references to the JDK from Sun and update them to reflect the IBM Developer Kit for Java. The section that I changed started as:
    
    [ -z "$JAVA_HOME" ]&& [ -d /usr/java ] && (
                export JAVA_HOME=/usr/java
                [ -r $JAVA_HOME/lib/classes.zip ] &&
                  export CLASSPATH=$JAVA_HOME/lib/classes.zip
    )
    

    Replace it with the following section to reflect the default locations for the IBM Developer Kit for Java:
    
    [ -z "$JAVA_HOME" ]&& [ -d /usr/jdk118 ] && (
                export JAVA_HOME=/usr/jdk118
                export PATH=$PATH:$JAVA_HOME/bin
                [ -r $JAVA_HOME/lib/classes.zip ] &&
                  export CLASSPATH=$JAVA_HOME/lib/classes.zip
    )
    


3.1.3. After installing DB2 on Caldera

This section contains instructions that you must follow after installing DB2.


3.3. Mandrake Linux 8.1

3.3.1. Before installing DB2 on Mandrake Linux

Preparing for the installation of DB2

  1. Install the pdksh-5.2.14-12mdk.i586.rpmpackage from the Mandrake LinuxCD-ROM #2 in the /Mandrake/RPMS2/directory. For example, log in as root, mount the CD-ROM, and enter the following command to install the pdkshpackage:
    bash# rpm ivh /mnt/cdrom/Mandrake/RPMS2/pdksh-5.2.14-12mdk.i586.rpm
  2. The Linux 2.4 kernel changes the default values of some ipc limits. However, the default value for the msgmniis 16, which causes difficulties running DB2 with the default 2.4 kernel ipc parameters. Fortunately, the 2.4 kernel also enables you to change a number of these parameters through the /procfilesystem. With the 2.4 kernel, you do not have to recompile your kernel to experiment with different parameter values. To set the msgmnikernel parameter at boot time, append the following lines to /etc/sysctl.conf:
    
# Sets maximum number of message queues to 128
    # Set this to 1024 or higher on production systems
    kernel.msgmni = 128
    
  3. Uninstall the default Mandrake Linux8.1 Kaffe Virtual Machine with Package Manager or Software Manager. Install the IBM Developer Kit for Javaby issuing the following command as root:
    bash# rpm -ivh IBMJava118-SDK-1.1.8-5.0-i386.rpm
  4. To set up the Java environment for all or specific users in Mandrake Linux 8.1, copy the content of /usr/jdk118/binto /usr/binand /usr/jdk118/libto /usr/lib. After that you can successfully issue the
    java -fullversion
    command.
  5. To install DB2 Warehouse Control Database, you must change the permissions for the /homedirectory to read, write and execute (for users, groups, others) as a user with root authority:
    
bash# chmod ugo=rwx /home
    
    If you do not change the permissions for the /homedirectory, you may recieve the following error: SQL0970N The system attempted to write to a read-only file. SQLSTATE=55009.

3.5. Red Hat Linux 7.1

3.5.1. Before installing DB2 on Red Hat

Preparing for the installation of DB2

  1. Install the pdksh-5.2.14-12.i386.rpm package from Red Hat CD-ROM (2) in the /RedHat/RPMS/ directory. For example, log in as root, mount the CD-ROM, and enter the following command to install the pdksh package:
    bash# rpm -ivh /mnt/cdrom/RedHat/RPMS/pdksh-5.2.14-12.i386.rpm

  2. For a compatible version of the libstdc++ library, install the compat-egcs-c++-6.2-1.1.2.14.i386.rpm package from Red Hat CD-ROM (2) in the /RedHat/RPMS/ directory. For example, log in as root, mount the CD-ROM, and enter the following command to install the compat-egcs-c++ package:
    bash# rpm -ivh /mnt/cdrom/RedHat/RPMS/compat-egcs-c++-6.2-1.1.2.14.i386.rpm

  3. Install the compat-libs-6.2-3.i386.rpm package from Red Hat CD-ROM (2) in the /RedHat/RPMS/ directory. For example, log in as root, mount the CD-ROM, and enter the following command to install the compat-libs package:
    bash# rpm -ivh /mnt/cdrom/RedHat/RPMS/compat-libs-6.2-3.i386.rpm

  4. The db2setup command looks for a file called /usr/lib/libncurses.so.4 and will not proceed unless it exists, so create a symbolic link from the ncurses4.0 library in /usr/i386-glibc21-linux/lib/ to your /usr/lib/ directory.
    
bash# ln -sf /usr/i386-glibc21-linux/lib/libncurses.so.4.0 /usr/lib/libncurses.so.4
    

  5. The default setting for the msgmni kernel parameter only allows a couple of simultaneous connections to DB2. To set this value at at boot time, append the following lines to /etc/sysctl.conf:
    
# Sets maximum number of message queues to 128
    # Set this to 1024 or higher on production systems
    kernel.msgmni = 128
    


3.5.2. Installing DB2 and creating instances on Red Hat

Follow the instructions in Section 4, the generic section on installing DB2 and creating instances.


4. Installing DB2 using db2setup

The purpose of this section is to walk you through a typical install of DB2 Version 7.1 on Linux. The following section, Section 6, tells you how to create both a DB2 Administration Server and a DB2 instance. For in-depth information on the components offered by DB2 Version 7.1, consult the following documents:

For the purposes of this document, I'll assume that you have a copy of DB2 Version 7.1 on CD-ROM. If you download a copy from IBM, just adjust the path /mnt/cdrom in the following instructions to reflect the directory created by the tar command.

Tip

Some distributions disable execute privileges on CD-ROM devices by default. To mount a CD-ROM with execute permissions at mount point /mnt/cdrom, issue the following command as root:

bash# mount -o exec /mnt/cdrom


4.2. Installing DB2 components

The following instructions assume that you are using db2setup to install DB2.

To select or deselect a component, highlight the component using the cursor keys and press ENTER.

To change the options for a component, highlight [ Customize... ] and press ENTER.

To install your selected components, highlight [ OK ] on the Install DB2 V7 menu and press ENTER.

The common DB2 files are installed in the /usr/IBMdb2/V7.1/ directory. When you create an instance, a directory called sqllib is created in the corresponding user's home directory. The sqllib directory contains symbolic links to the executables and other files in /usr/IBMdb2/V7.1/.

The following list describes some of the common DB2 components that you can install, including estimates of the size required for each component.

Description of DB2 components

Administration Client

The Administration Client enables database administrators to administer local or remote DB2 servers from the command line. This component, without Java support or the Control Center, requires about 20 MB of disk space.

Control Center

The Control Center (db2cc) is an optional part of many DB2 components. It gives database administrators a graphical interface for administering local or remote DB2 servers. The Control Center includes the DB2 Information Center (db2ic), which gives you a graphical interface that provides a tree view of the DB2 documentation installed on your workstation organized by task or by title.

Note that both the Control Center and Information Center are Java applications, so their performance depends on your system's processor speed and available memory. This component requires about 90 MB of disk space.

Tip

You probably want to install the Control Center.

DB2 UDB Enterprise Edition, DB2 UDB Workgroup Edition, DB2 Personal Edition

These components determine the state of your DB2 installation as a database server. The core capabilities of the components are the same. The difference between Enterprise Edition and Workgroup Edition primarily has to do with how they are licensed--Enterprise Edition is licensed on a per-processor basis with unlimited users, while Workgroup Edition is licensed on a per-user basis. Enterprise Edition also gives you the capability to enable DB2 clients to connect to mainframe databases, like DB2 for OS/390 or DB2 for OS/400. In contrast, Personal Edition is a single user database server that is useful only for developing DB2 applications. You cannot use Personal Edition as a server because Personal Edition does not accept incoming remote connections.

Adding one of these components requires about 40 MB of disk space.

Application Development Client

The Application Development Client component installs the headers and libraries that you need to create applications using embedded SQL for C and C++, Call Level Interface (CLI), Java Database Connectivity (JDBC), or embedded SQL for Java (SQLJ). You also have the option of installing the source code for sample applications that demonstrate much of the functionality of DB2.

Tip

If you plan on developing applications for DB2, install the sample applications. The sample directories in /usr/IBMdb2/V7.1/samples/ contain build scripts (bld***) that include the compile and link options suitable for your own applications.

Tip

If you are trying to develop applications and you get an error like "That command is not supported in this environment" while trying to precompile a file, it's because you either did not install the Application Development Client, or you installed it after you created an instance and you have not used the db2iupdt command to update the instance. See Section 9.1 for more information on db2iupdt.

Including the sample applications, this component requires about 10 MB of disk space.

DB2 Product Library (HTML documentation)

Documentation is installed into the /usr/IBMdb2/V7.1/doc/ directory. For each language that you install, the DB2 installer creates a subdirectory with a five-character name corresponding to the language locale. Issue the db2help command to fire up your Web browser with a page that links to the documentation installed with DB2.

The English HTML (En_US) documentation requires about 90 MB of disk space.


5. Installing DB2 on other Linux distributions

DB2 Version 7.1 is distributed as a set of RPM packages. If you want to install DB2 on a distribution that is not officially supported by IBM, and that distribution satisfies all of the prerequisites specified in Section 2, all that you theoretically need to do is find a way to install those packages on your distribution. The alien utility available from Kite converts RPM packages into formats supported by Debian (dpkg), Stampede (slp), and Slackware (slp).

Debian

Susan Williams reported success in installing DB2 Version 7.1 on Debian using the following script as root:

This script installs every DB2 package on the CD-ROM. In a future iteration of this document I plan to provide a description of all of the DB2 packages to help you develop a more selective approach for your installation.

Christoph Shmitz reports that, while he was able to install DB2 Version 7.1 Personal Developer's Edition on Debian 2.2 using alien as described above, DB2 starts in a time-limited trial mode (90 days). While the use of DB2 Version 7.1 Personal Developer's Edition should be unlimited, alien does not automatically install the DB2 license file.

To remove the time limit on DB2 Version 7.1 Personal Developer's Edition, you need to manually install the license file (s000510.personal/db2/license/db2udbpe.lic in the tar archive) using the following command as root:

bash# db2licm -a db2udbpe.lic

Using alien apparently prevents you from using the db2setup command to create instances. To create a DB2 Administration Server from the command line, issue the /usr/ibmdb2/v7.1/instance/dasicrt command as root. To create a DB2 instance, issue the /usr/ibmdb2/v7.1/instance/db2icrt command as root. To get the correct syntax for either command, use the -h flag.

In the following section, Andika Triwidada describes how to install DB2 on Debian 2.2 using the rpm command. You can check the prerequisite package levels (described in Section 2) installed on your system with the following command:

bash$ dpkg -l|egrep -e '(libc6|libstdc++|pdksh|rpm|zip)'|awk '{print $1,$2,$3}'
The resulting list should contain:

  ii  libc6                 2.1.3-13
  ii  libstdc++2.9-glibc2.1 2.91.66-4
  ii  pdksh                 5.2.14-1
  ii  rpm                   3.0.3-1
  ii  unzip                 5.40-1

If you are missing any of these packages, you can install the package using apt-get:

bash# apt-get install package-name

Installation Steps

  1. Initialize the RPM database.
    
bash# rpm --initdb
    

  2. Modifiy several files in /bin
    
bash# mv /bin/sh /bin/sh.bash
    bash# ln -s /usr/bin/ksh /bin/sh
    bash# for f in awk basename ksh passwd sort touch; do ln -s /usr/bin/$f /bin/$f; done
    

  3. Copy the contents of the following script to create an RPM wrapper called /bin/rpm.
    
#!/bin/sh
    # RPM wrapper, force RPM installation without checking any dependencies
    if [ "$1" = "-ivh" ]
    then
      shift
     /usr/bin/rpm -ivh --nodeps $*
    else
     /usr/bin/rpm $*
    fi
    

  4. Make the RPM wrapper executable:
    
bash# chmod +x /bin/rpm
    

  5. Install DB2 using the db2setup command by following the instructions in Section 4.

  6. Create the DB2 administration server and at least one DB2 instance as described in Section 6. To simplify testing, ensure that you create the sample database when you create the DB2 instance.

Testing your DB2 installation

  1. Log on to your Linux server with the DB2 instance user ID. Remember, the default user ID is db2inst1.

  2. Prepare your DB2 environment by running the db2profile script:
    
bash$ cd ~/sqllib
    bash$ . ./db2profile
    

  3. Run a query against the sample database to test your installation.
    
bash$ db2
    bash$ db2 => connect to sample
    bash$ db2 => select * from employee
    
    There should be a printout of records from sample database here
    
bash$ db2 => quit
    

After you install DB2

  1. Remove the RPM wrapper script by removing, renaming, or linking it directly to /usr/bin/rpm.
    
bash# rm /bin/rpm
    

  2. Change /bin/sh back into a symlink to /usr/bin/bash.
    
bash# ln -sf /usr/bin/bash /bin/sh
    

After installing DB2 with alien, Claus Reiner reported that:

While all components of DB/2 were installed, the instance apparently didn't know them and thus couldn't use them. After a lot of sweat going through the configurations, IBM support told me that I should make an instance update which solved it. (The instance could locally and between Unixen do everything, only when trying to connect to AS/400 using DCS it told us 'authentication not supported').

Claus recommends running the following commands as root after installing DB2 with either alien or RPM,

bash# . $INSTANCEHOME/sqllib/db2profile
bash# /usr/IBMdb2/V7.1/instance/db2iupdt -e


6. Creating DB2 instances

This section gives you a brief overview of DB2 instances and the DB2 Administration Server, and tells you how to create them.

Some IBM documentation uses the term "instance" to refer to both DB2 instances and a DB2 Administration Server. The basic similarity between a DB2 Administration Server and a DB2 instance, or "database manager", is that each is associated with a unique user ID. When you create either a DB2 instance or a DB2 Administration Server, DB2:


6.2. Overview of DB2 instance

To quote the IBM DB2 Universal Database Version 7.1 Administration Guide definition of an instance:

An instance (sometimes called a database manager) is DB2 code that manages data. It controls what can be done to the data, and manages system resources assigned to it. Each instance is a complete environment. ... An instance has its own databases (which other instances cannot access), and all its database partitions share the same system directories. It also has separate security from other instances on the same machine (system).

What this boils down to is that for every DB2 instance, DB2 requires a unique user ID on your Linux workstation. Security for an instance is provided by the normal password authentication process for any Linux user ID. Each instance can contain one or more databases, each of which inherits settings from their instance.

Creating the Administration Server using db2setup

The DB2 Administration Server requires about 3 MB of disk space. The following steps guide you through the process of creating a DB2 Administration Server.

  1. Issue the db2setup command as described in Section 4.2.

  2. Select [ Create... ].

  3. Select the check box for Create the Administration Server. The Administration Server window is displayed.

  4. Enter a unique user name in the User Name field. You can use an existing user name that is not already in use by a DB2 instance, but it is probably simpler to create a new user for each instance.

  5. Select the Use default UID check box. As far as I can tell, this setting is always right.

  6. Enter a unique group name in the Group Name field. You can use an existing group name if you wish, but creating a new group ensures that you do not inadvertently give permissions to other users on your system.

  7. Select the Use default GID check box. Again, as far as I can tell, this setting is always right.

  8. Ensure that the value of the Home Directory field reflects the home directory of the user ID.

    Warning

    SuSE users: The prefix for the home directory may default to /usr/lib/db2/. This is almost certainly wrong; the value for a standard SuSE system should be /home/.

  9. Enter a unique password in the Password and Verify Password fields.

    Warning

    Enter a new password! If you do not enter a new password in these fields, DB2 assigns the default password ibmdb2, giving crackers a wide-open front door to your system.

Creating a DB2 instance using db2setup

A DB2 instance requires about 2 MB of disk space. A sample database for a DB2 instance requires about 16 MB of disk space. The following steps guide you through the process of creating a DB2 instance.

  1. Issue the db2setup command as described in Section 4.2.

  2. Select [ Create... ].

  3. Select the Create a DB2 Instance check box. The DB2 Instance window is displayed.

  4. Enter a unique user name in the User Name field. You can use an existing user name that is not already in use by a DB2 instance, but it is probably simpler to create a new user for each instance.

  5. Select the Use default UID check box. As far as I can tell, this setting is always right.

  6. Enter a unique group name in the Group Name field. You can use an existing group name if you wish, but creating a new group ensures that you do not inadvertently give permissions to other users on your system.

  7. Select the Use default GID check box. Again, as far as I can tell, this setting is always right.

  8. Ensure that the value of the Home Directory field reflects the home directory of the user ID.

    Warning

    SuSE users: The prefix for the home directory may default to /usr/lib/db2/. This is almost certainly wrong; the value for a standard SuSE system should be /home/.

  9. Enter a unique password in the Password and Verify Password fields.

    Warning

    Enter a new password! If you do not enter a new password in these fields, DB2 assigns the default password ibmdb2, giving crackers a wide-open front door to your system.

  10. Select [ Properties... ] to change the properties for the instance.

    1. Under the Authentication Type heading, select the Server Encrypt check box. This greatly improves the security of your system, by telling DB2 to accept encrypted passwords, rather than plain text passwords.

    2. Select the Auto start DB2 Instance at system boot check box if you want to start this DB2 instance every time you reboot your system.

    3. Select the Create a sample database for DB2 Instance check box if you plan to work with the sample applications available with the Application Development Client. To run correctly, most of the sample applications require the specific tables and data of the sample database. If you do not create the sample database now, you can create it later using the db2sampl command.

  11. Select [ OK ] to create the DB2 instance. The Fenced User text window is displayed. Repeat the previous steps for creating a new user and group. Server-side DB2 executables, such as stored procedures and user-defined functions, execute under the permissions of the fenced user ID. By controlling the permissions of the fenced user ID, you control the permissions of the server-side DB2 executables.

  12. Select [ OK ] to create the fenced user.


7. Removing DB2

To remove DB2 from your workstation cleanly, perform the following steps:


8. Using DB2

This section gives you the basic information you need to start working with DB2 on Linux. It includes instructions on issuing DB2 commands and SQL statements from the command line, as well as the commands you need to start the DB2 Control Center and the DB2 Information Center.

Note

This section assumes that you have followed the instructions in Section 11.


8.3. The DB2 command line

If you are logged on to your Linux workstation using either the DB2 Administration Server user ID or the DB2 instance user ID, you can issue DB2 commands and SQL statements from the command line.

If this is your first time using DB2, I would suggest creating the sample database that ships with DB2. The sample database is used throughout the DB2 documentation and is required by most of the sample applications. To create the sample database, you can either select the Create the sample database option when you create a DB2 instance, or issue the db2sampl command from the DB2 command line.

Before you can issue an SQL statement, you have to connect to a database. To connect to a database:

To connect to a database, and have DB2 prompt you for the password:

  • db2 CONNECT TO database USER userID

To connect to a database using the default user ID:

  • db2 CONNECT TO database

Once you have connected to a database, you can then issue SQL statements or DB2 commands against that database. For example, to select all of the columns from the EMPLOYEE table in the SAMPLE database, issue the following command:
bash$ db2 "SELECT * FROM employee"

Note

You can avoid typing db2 as the prefix for every SQL statement and DB2 command by issuing commands using the Command Line Processor (CLP). To start the CLP, issue the db2 command by itself. DB2 provides the following prompt:

You can issue database manager commands and SQL statements from the command
prompt. For example:
    db2 => connect to sample
    db2 => bind sample.bnd

For general help, type: ?.
For command help, type: ? command, where command can be
the first few keywords of a database manager command. For example:
 ? CATALOG DATABASE for help on the CATALOG DATABASE command
 ? CATALOG          for help on all of the CATALOG commands.

To exit db2 interactive mode, type QUIT at the command prompt. Outside
interactive mode, all commands must be prefixed with 'db2'.
To list the current command option settings, type LIST COMMAND OPTIONS.

For more detailed help, refer to the Online Reference Manual.

db2 =>

I don't use the CLP because it prevents me from using the command line history feature of my shell. I find myself using the command line history a lot when I'm issuing SQL statements.

Some users claim that running the CLP within an Emacs shell gives them the best of both worlds: they get command line history, and they don't have to escape commands that contain lots of quotation marks and brackets.


9. Troubleshooting

The following section covers some of the common problems you may encounter while installing DB2, creating an instance, or using a DB2 database.


9.1. Problems with DB2 installation

The following section covers some of the common problems you may encounter when you install DB2.

9.1.1. When I try to run db2setup, I get the following error: DBI1503E An error was encountered when opening or writing to file, "/tmp/.dbinst.swp".
9.1.2. When I try to run db2setup, I get the following error: ./db2inst: error while loading shared libraries: libncurses.so.4: cannot open shared object file: No such file or directory
9.1.3. Creating a DB2 instance on SuSE Linux: Default user name already exists
9.1.4. Creating a DB2 instance on SuSE Linux: Default group name already exists
9.1.5. Creating a DB2 instance on SuSE Linux: Default home directory points to /usr/lib/db2/
9.1.6. After creating a DB2 instance, I installed the Application Development Client, but I can't use that instance to create DB2 applications.
9.1.7. I installed DB2, but none of the permissions in /usr/IBMdb2/V7.1/bin are executable!

If you did not remove the default DB2 user IDs created by SuSE Linux before installing DB2 (see Section 3.6), the DB2 Create Instance panel places the corresponding user ID in the "User ID" field. This can cause a problem when you change the value of the User Name field to reflect the name of the new instance, because the value of the "User ID" still reflects the original user name.

Ensure that you select the "Use default UID" check box to automatically associate the new user name with its corresponding user ID.

If you did not remove the default DB2 user IDs created by SuSE Linux before installing DB2 (see Section 3.6), the DB2 Create Instance panel places the corresponding group ID in the Group ID field. This can cause a problem when you change the value of the Group Name field to reflect the name of the new instance, because the value of the Group ID still reflects the original group name.

Ensure that you select the "Use default GID" check box to automatically associate the new group name with its corresponding group ID.

If you did not remove the default DB2 user IDs created by SuSE Linux before installing DB2 (see Section 3.6), the default user name already exists and was created in the /usr/lib/db2/ directory. To change the home directory of your new DB2 instance, you must manually specify the location of the new instance. The default home directory is /home/.

When you create an instance, as described in Section 6, DB2 copies selected files from /usr/IBMdb2/V7.1/bin into the $HOME/sqllib/bin directory of the instance. DB2 sets the appropriate permissions on the copies of the files in the instance directory.


9.2. Problems creating a DB2 instance

The following section covers some of the common problems you may encounter when you create a DB2 instance.

9.2.1. Creating a DB2 instance or a DB2 Administration Server fails.
9.2.2. db2setup indicated that it successfully created an instance, but I checked /tmp/db2install.log and it contains the message DBI1766W Cannot change the secondary group list of "" (Caldera OpenLinux 2.4).

9.3. Problems using DB2

The following section covers some of the common problems you may encounter when you use a DB2 database.

9.3.1. DB2 is running out of available connections.
9.3.2. I installed DB2 Version 6.1 and db2start just hangs.
9.3.3. I'm using DB2 PE 7.1 on linux (RH 6.0), and I'm having problems when trying to connect with my username and password. I can connect successfully to the database with the default user ID:

bash$ db2 connect to sample

Database Connection Information

Database server        = DB2/LINUX 7.1.0
SQL authorization ID   = userID
Local database alias   = SAMPLE
But when I try to connect to the database using the explicit user ID, it fails:

bash$ db2 CONNECT TO sample USER userID
Enter current password for userID:
SQL1403N  The username and/or password supplied is incorrect.
SQLSTATE=08004
Why can't I connect with an explicit user ID?
9.3.4. When I run any db2 commands, part of the output is Welcome to your OpenLinux system!. How do I change this? (Caldera OpenLinux 2.4)
9.3.5. How do I connect from a DB2 Connect for Linux client to a DB2 for AS/400 server?

9.4. Problems starting the DB2 Control Center

The following section covers some of the common problems you may encounter trying to start the DB2 Control Center.

9.4.1. When I start the DB2 Control Center with db2cc, nothing happens.
9.4.2. When I start the DB2 Control Center, I get a message box with the error SQL1042C An unexpected system error occurred.
9.4.3. I followed the instructions for installing IBM JDK 1.1.8 but Java applications, including the DB2 Control Center, don't work.
9.4.4. The DB2 Control Center starts normally, but the "Systems" folder is empty.
9.4.5. When I try to start the DB2 Control Center, I get the following message at the console: Xlib: connection to "localhost:0.0" refused by server
9.4.6. When I start the DB2 Control Center, I get a message box with the error SQL1042C An unexpected system error occurred.
9.4.7. When I try to start the DB2 Control Center with the db2cc command, the splash screen comes up, then disappears.

Ensure that you have installed the IBM Developer Kit for Java, and that the directory containing the jre or java executable is in your path. If you issue the command
bash$ java -fullversion
, you should get a response like this: java full version "JDK 1.1.8 IBM build l118-20000325 (JIT enabled: jitc)" or, for the IBM JDK 1.3: java full version "J2RE 1.3.0 IBM build cx130-20000623" Java virtual machines from other sources may not work. For a quick guide to installing the IBM Developer Kit for Java, see Section 11.


10. Improving DB2 Version 7.1 performance on Linux

Database administrators running DB2 on Linux often run into problems attempting to perform the following tasks:

The following sections attempt to address those problems.


10.1. Increasing maximum connections

One of the most frequently reported problems with running DB2 on Linux is that DB2 seems to quickly start refusing connections to the server. You can alleviate this problem by examining an altering several kernel parameters that control inter-process communication (ipc) limits.

The number of connections that DB2 can support depends on kernel parameters that, in the 2.2 kernel, are #define variables included in the kernel source header files. In the 2.4 kernel, some of these parameters can be set through the /proc filesystem. Following the description of these variables is a table listing the default values by distribution. The table includes the values of these variables in the updated kernel packages for each distribution.

_SHM_ID_BITS

This variable, defined in /usr/src/linux/include/asm/shmparam.h, determines the number of shared memory segment identifiers available to Linux. The default value for _SHM_ID_BITS in the kernel source is 7, which allows for a total of 2^7, or 128, shared memory segment identifiers.

On a single-processor machine, DB2 itself uses a set number (~15) of shared memory segment identifiers. On a machine with multiple processors, DB2 also requires one shared memory segment identifier per agent to take advantage of the Fast Communication Manager (FCM) feature of DB2. Because each DB2 connection requires one agent per processor, on a quad-processor machine the default value of _SHM_ID_BITS allows less than 32 simultaneous connections to a DB2 instance.

If you recompile the kernel yourself, you should be able to safely increase this value to 9.

MSGMNI

This variable determines the maximum number of message queue identifiers. For DB2 Version 7.1 to function correctly, the minimum value is 128, but for heavier use consider setting this value to 1024 or higher.

In the 2.2 kernel source, this variable is defined in /usr/src/linux/include/linux/msg.h. The default value of 128 is acceptable for small-scale use of DB2 Version 7.1.

In the 2.4 kernel source, this variable is defined in /proc/sys/kernel/msgmni. The default value of 16 must be increased to enable DB2 Version 7.1 to function correctly. The good news is that you can change this value without recompiling the kernel or rebooting your machine. For more information, see Section 12.

NR_TASKS

This variable, defined in /usr/src/linux/include/linux/tasks.h, determines the number of simultaneous processes that Linux supports. A second variable, MAX_TASKS_PER_USER, is defined as NR_TASKS/2. Since DB2 instances are treated as users by Linux, and each connection uses a single process, the maximum number of connections per instance is capped at the value of NR_TASKS/2.

The default value for NR_TASKS in the kernel source is 512, allowing a maximum of 256 simultaneous connections to a single DB2 instance. DB2 itself requires a few connections for overhead processes. If you recompile the kernel yourself, you should increase this value to something like 2048. The stock kernels shipped with the Red Hat, SuSE, and TurboLinux distributions increase the value of NR_TASKS to 2560 or above. However, Caldera OpenLinux eDesktop 2.4 ships with a kernel in which NR_TASKS is set to the default value of 512. Caldera users should increase the value of this variable and recompile the kernel.

SEMMNI

This variable, defined in /usr/src/linux/include/linux/sem.h, determines the number of semaphore identifiers that Linux supports. This variable is particularly important on symmetric multi-processing (SMP) machines. A unique semaphor identifier is required for each processor per agent (or connection); therefore, on a quad-processor machine, four semaphore identifiers are required per connection.

The default value for SEMMNI in the kernel source is 128, which, on a quad-processor machine, will only allow 32 simultaneous connections to a DB2 instance. If you recompile the kernel yourself, increase this value to something like 1024.

The following table shows the default values of the kernel parameters set in the stock kernel source and in the kernels provided by each distribution.

  • unknown indicates that I don't know what the default level is, probably because it came to my attention after I had already removed the distribution (your feedback is welcome!)

  • ?? indicates that I could not find the parameter in the kernel source or in the /proc/sys/kernel/ directory. Help, anyone?

  • ** as a prefix indicates that the default value is not acceptable and must be increased


11. Installing the IBM Developer Kit for Java

This section gives you quick and dirty instructions on how to install the IBM Developer Kit for Java, version 1.1.8 or 1.3. You need the IBM Developer Kit for Java to run the DB2 Control Center or Java applications or applets that connect to DB2. Note that these instructions are not meant to replace the documentation supplied with the IBM Developer Kit for Java.

Warning

For DB2 Version 7.1, you cannot use other versions of Java. Versions of the Java Virtual Machine (JVM) supplied by other software organizations are not supported.

Installing the IBM Developer Kit for Java, Version 1.1.8

  1. Download the IBM Developer Kit for Java, version 1.1.8, from the IBM Java Developer's Kit downloads web site. I'll assume that you download the RPM package of the IBM Developer Kit for Java.

  2. Install the IBM Developer Kit for Java by issuing the following command as root:
    bash# rpm -ivh IBMJava118-SDK-1.1.8-2.0-i386.rpm

    I most recently tested IBM JDK 1.1.8 build 20010115a successfully on Red Hat 6.2. To see which build of the IBM JDK you are using, issue the java -fullversion command.

  3. Add the following lines to your /etc/profile file to set up the Java environment for all users:
    
   export JAVA_HOME=/usr/jdk118
       export PATH=$PATH:$JAVA_HOME/bin
       export CLASSPATH=$CLASSPATH:$JAVA_HOME/lib/classes.zip
    

    Note

    Caldera users should see Section 3.1.1 for instructions on configuring the IBM Developer Kit for Java on Caldera OpenLinux.

    Note

    Red Hat 7.1 enabled a floating stack feature in the glibc library that breaks the IBM JDK 1.1.8. Other distributions might follow their lead. If the DB2 Control Center refuses to start successfully or your Java applications do not work, you can disable the floating stack by setting the LD_ASSUME_KERNEL environment variable to 2.2.5 before running the DB2 Control Center as follows:
    
bash$ export LD_ASSUME_KERNEL=2.2.5
    bash$ db2set DB2ENVLIST=LD_ASSUME_KERNEL
    
    It would probably be wise to include these commands in the sqllib/db2profile script of your instance user so that you always inherit these settings.

Installing the IBM Developer Kit for Java, Version 1.3

  1. Download the IBM Developer Kit for Java, version 1.3, from the IBM Java Developer's Kit downloads web site. I'll assume that you download the RPM package of the IBM Developer Kit for Java.

  2. Install the IBM Developer Kit for Java by issuing the following command as root:
    bash# rpm -ivh IBMJava2-SDK-1.3-1.1-i386.rpm

    I most recently tested build cx130-20010329 successfully with Red Hat 7.1. To see which build of the IBM JDK you are using, issue the java -fullversion command.

  3. Add the following lines to your /etc/profile file to set up the Java environment for all users:
    
   export PATH=$PATH:/opt/IBMJava2-13/jre/bin
    

    Note

    Caldera users should see Section 3.1.1 for instructions on configuring the IBM Developer Kit for Java on Caldera OpenLinux.

  4. IBM JDK 1.3 does away with the jre command, even if you install the the IBM JRE 1.3 package. However, the db2cc script calls the jre command. The easiest solution is to create a link called jre to the java executable in the /opt/IBMJava2-13/bin directory by issuing the following command as root.
    
bash# ln -sf /opt/IBMJava2-13/jre/bin/java /opt/IBMJava2-13/jre/bin/jre
    

  5. The db2cc script calls the jre command with the -nojit argument, which is not supported in IBM JDK 1.3. Remove the option by changing line 44 of /usr/IBMdb2/V7.1/bin/db2cc to the following:
    
JRE_OPTIONS="-ss256k -mx128m -Ddb2path=$DB2PATH"
    


12. Using the 2.4 kernel with DB2 Version 7.1

The Linux 2.4 kernel changes the default values of some ipc limits. However, the default value for the msgmni is 16, which causes difficulties running DB2 with the default 2.4 kernel ipc parameters. Fortunately, the 2.4 kernel also enables you to change a number of these parameters through the /proc filesystem. With the 2.4 kernel, you do not have to recompile your kernel to experiment with different parameter values.

Configure the msgmni parameter by issuing the sysctl command as root:

bash# sysctl -w kernel.msgmni=128
You can also change values directly in /proc/sys/kernel using the echo command:

bash# echo "128" > /proc/sys/kernel/msgmni

To set the msgmni kernel parameter at boot time, append the following lines to /etc/sysctl.conf:

# Sets maximum number of message queues to 128
# Set this to 1024 or higher on production systems
kernel.msgmni = 128
To check the current ipc settings, issue the ipcs -l command:

bash$ ipcs -l

------ Shared Memory Limits --------
max number of segments = 4096
max seg size (kbytes) = 32768
max total shared memory (kbytes) = 8388608
min seg size (bytes) = 1

------ Semaphore Limits --------
max number of arrays = 128
max semaphores per array = 250
max semaphores system wide = 32000
max ops per semop call = 32
semaphore max value = 32767

------ Messages: Limits --------
max queues system wide = 128
max size of message (bytes) = 8192
default max size of queue (bytes) = 16384


A. Resources

Following is a list of references to further information on using DB2 V7.1 for Linux:

Mailing lists and newsgroups

comp.databases.ibm-db2

Covers the use of DB2 Universal Database on all platforms, including Linux and other Unices, OS/2, OS/390, OS/400, and Windows. This forum is quite active.

DB2 Email User Group

This mailing list claims about 300 subscribers who ask and answer questions. The site provides a link to searchable archives, and sharing of utilities and scripts is encouraged.

ibm.software.db2.udb.v7beta on the news.software.ibm.com NNTP server

Although this newsgroup was meant to serve users trying out the DB2 V7.1 beta code, there are a lot of general questions about DB2 on Linux that might help answer your questions. Now that the final release is available, activity on this forum has slowed down significantly.

Web sites

DB2 Library

IBM publishes many books on installing, administering, and developing applications with DB2. If you decide not to install the documentation when you install DB2, you can always access the documentation online in HTML format or download PDF versions of the books.

DB2 Application Development

This web site contains the latest information about restrictions, workarounds, or additional documentation for developing applications with DB2.

DB2 for Linux

This web site contains general information about using DB2 for Linux, including a link to the free download of DB2 Personal Developers Edition.

DB2 Magazine

This web site is the online version of DB2 Magazine, which publishes articles about using DB2 on Linux and other platforms. You can also sign up a free subscription to the print version of the magazine.

DB2 White Papers

This web site contains white papers published by IBM about DB2. White papers typically provide overviews or introductions to new technology or new releases of a product.

International DB2 Users Group (IDUG)

IDUG holds a number of international conferences on DB2 and has regional user groups. While IDUG has traditionally focused on DB2 for OS/390 and OS/400, they have increasingly included information on DB2 for Linux, other Unices, OS/2, and Windows. The IDUG web site includes online discussion forums and links to other DB2 resources.

DB2 on Debian

Andika Triwidada contributed most of the information in this document about installing DB2 on Debian, using rpm to install the DB2 packages. The web page is the original source of that information. For those interested in installing previous releases of DB2 for Linux on Debian, Andika also includes information on running DB2 Version 5.2 and DB2 Version 6.1 on Debian.

DbtuTools project

Daniel Scheibli has started a project with the following mission statement:

The mission of DbtuTools is to become an framework for working with the Wintel/UNIX versions of IBM's DB2 UDB database family. Starting with an modest tool collection ("little helpers for daily work") the long-term goal is to extend the project in a way that it becomes an integrated solution.

The project provides tools that help DB2 administrators to understand the db2diag.log file, display extensive information about current connections, and provide a comprehensive list of information about the tablespaces and tablespace containers.

Full text searching with DB2 on Linux and SWISH++

The Net Search Extender, formerly known as the Text Extender, allows you to perform full-text indexing and searches of databases on DB2.

Before Net Search Extender was available for DB2 for Linux, Kevin Sangalee put together an excellent page on an alternative method of providing similar function. From the site:

This document describes way to provide this functionality using the text indexing package SWISH++, a User Defined Function (in this case, written in C), and a Perl script. It should be taken as an overview guide rather than as detailed instructions, since the solution may require some coercing to fit with other applications.


B. GNU General Public License

Version 2, June 1991

Copyright (C) 1989, 1991 Free Software Foundation, Inc. 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.


B.1. Preamble

The licenses for most software are designed to take away your freedom to share and change it. By contrast, the GNU General Public License is intended to guarantee your freedom to share and change free software--to make sure the software is free for all its users. This General Public License applies to most of the Free Software Foundation's software and to any other program whose authors commit to using it. (Some other Free Software Foundation software is covered by the GNU Library General Public License instead.) You can apply it to your programs, too.

When we speak of free software, we are referring to freedom, not price. Our General Public Licenses are designed to make sure that you have the freedom to distribute copies of free software (and charge for this service if you wish), that you receive source code or can get it if you want it, that you can change the software or use pieces of it in new free programs; and that you know you can do these things.

To protect your rights, we need to make restrictions that forbid anyone to deny you these rights or to ask you to surrender the rights. These restrictions translate to certain responsibilities for you if you distribute copies of the software, or if you modify it.

For example, if you distribute copies of such a program, whether gratis or for a fee, you must give the recipients all the rights that you have. You must make sure that they, too, receive or can get the source code. And you must show them these terms so they know their rights.

We protect your rights with two steps: (1) copyright the software, and (2) offer you this license which gives you legal permission to copy, distribute and/or modify the software.

Also, for each author's protection and ours, we want to make certain that everyone understands that there is no warranty for this free software. If the software is modified by someone else and passed on, we want its recipients to know that what they have is not the original, so that any problems introduced by others will not reflect on the original authors' reputations.

Finally, any free program is threatened constantly by software patents. We wish to avoid the danger that redistributors of a free program will individually obtain patent licenses, in effect making the program proprietary. To prevent this, we have made it clear that any patent must be licensed for everyone's free use or not licensed at all.

The precise terms and conditions for copying, distribution and modification follow.


B.1.1. GNU GENERAL PUBLIC LICENSE TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION

0. This License applies to any program or other work which contains a notice placed by the copyright holder saying it may be distributed under the terms of this General Public License. The "Program", below, refers to any such program or work, and a "work based on the Program" means either the Program or any derivative work under copyright law: that is to say, a work containing the Program or a portion of it, either verbatim or with modifications and/or translated into another language. (Hereinafter, translation is included without limitation in the term "modification".) Each licensee is addressed as "you".

Activities other than copying, distribution and modification are not covered by this License; they are outside its scope. The act of running the Program is not restricted, and the output from the Program is covered only if its contents constitute a work based on the Program (independent of having been made by running the Program). Whether that is true depends on what the Program does.

1. You may copy and distribute verbatim copies of the Program's source code as you receive it, in any medium, provided that you conspicuously and appropriately publish on each copy an appropriate copyright notice and disclaimer of warranty; keep intact all the notices that refer to this License and to the absence of any warranty; and give any other recipients of the Program a copy of this License along with the Program.

You may charge a fee for the physical act of transferring a copy, and you may at your option offer warranty protection in exchange for a fee.

2. You may modify your copy or copies of the Program or any portion of it, thus forming a work based on the Program, and copy and distribute such modifications or work under the terms of Section 1 above, provided that you also meet all of these conditions:

a) You must cause the modified files to carry prominent notices stating that you changed the files and the date of any change.

b) You must cause any work that you distribute or publish, that in whole or in part contains or is derived from the Program or any part thereof, to be licensed as a whole at no charge to all third parties under the terms of this License.

c) If the modified program normally reads commands interactively when run, you must cause it, when started running for such interactive use in the most ordinary way, to print or display an announcement including an appropriate copyright notice and a notice that there is no warranty (or else, saying that you provide a warranty) and that users may redistribute the program under these conditions, and telling the user how to view a copy of this License. (Exception: if the Program itself is interactive but does not normally print such an announcement, your work based on the Program is not required to print an announcement.)

These requirements apply to the modified work as a whole. If identifiable sections of that work are not derived from the Program, and can be reasonably considered independent and separate works in themselves, then this License, and its terms, do not apply to those sections when you distribute them as separate works. But when you distribute the same sections as part of a whole which is a work based on the Program, the distribution of the whole must be on the terms of this License, whose permissions for other licensees extend to the entire whole, and thus to each and every part regardless of who wrote it.

Thus, it is not the intent of this section to claim rights or contest your rights to work written entirely by you; rather, the intent is to exercise the right to control the distribution of derivative or collective works based on the Program.

In addition, mere aggregation of another work not based on the Program with the Program (or with a work based on the Program) on a volume of a storage or distribution medium does not bring the other work under the scope of this License.

3. You may copy and distribute the Program (or a work based on it, under Section 2) in object code or executable form under the terms of Sections 1 and 2 above provided that you also do one of the following:

a) Accompany it with the complete corresponding machine-readable source code, which must be distributed under the terms of Sections 1 and 2 above on a medium customarily used for software interchange; or,

b) Accompany it with a written offer, valid for at least three years, to give any third party, for a charge no more than your cost of physically performing source distribution, a complete machine-readable copy of the corresponding source code, to be distributed under the terms of Sections 1 and 2 above on a medium customarily used for software interchange; or,

c) Accompany it with the information you received as to the offer to distribute corresponding source code. (This alternative is allowed only for noncommercial distribution and only if you received the program in object code or executable form with such an offer, in accord with Subsection b above.)

The source code for a work means the preferred form of the work for making modifications to it. For an executable work, complete source code means all the source code for all modules it contains, plus any associated interface definition files, plus the scripts used to control compilation and installation of the executable. However, as a special exception, the source code distributed need not include anything that is normally distributed (in either source or binary form) with the major components (compiler, kernel, and so on) of the operating system on which the executable runs, unless that component itself accompanies the executable.

If distribution of executable or object code is made by offering access to copy from a designated place, then offering equivalent access to copy the source code from the same place counts as distribution of the source code, even though third parties are not compelled to copy the source along with the object code.

4. You may not copy, modify, sublicense, or distribute the Program except as expressly provided under this License. Any attempt otherwise to copy, modify, sublicense or distribute the Program is void, and will automatically terminate your rights under this License. However, parties who have received copies, or rights, from you under this License will not have their licenses terminated so long as such parties remain in full compliance.

5. You are not required to accept this License, since you have not signed it. However, nothing else grants you permission to modify or distribute the Program or its derivative works. These actions are prohibited by law if you do not accept this License. Therefore, by modifying or distributing the Program (or any work based on the Program), you indicate your acceptance of this License to do so, and all its terms and conditions for copying, distributing or modifying the Program or works based on it.

6. Each time you redistribute the Program (or any work based on the Program), the recipient automatically receives a license from the original licensor to copy, distribute or modify the Program subject to these terms and conditions. You may not impose any further restrictions on the recipients' exercise of the rights granted herein. You are not responsible for enforcing compliance by third parties to this License.

7. If, as a consequence of a court judgment or allegation of patent infringement or for any other reason (not limited to patent issues), conditions are imposed on you (whether by court order, agreement or otherwise) that contradict the conditions of this License, they do not excuse you from the conditions of this License. If you cannot distribute so as to satisfy simultaneously your obligations under this License and any other pertinent obligations, then as a consequence you may not distribute the Program at all. For example, if a patent license would not permit royalty-free redistribution of the Program by all those who receive copies directly or indirectly through you, then the only way you could satisfy both it and this License would be to refrain entirely from distribution of the Program.

If any portion of this section is held invalid or unenforceable under any particular circumstance, the balance of the section is intended to apply and the section as a whole is intended to apply in other circumstances.

It is not the purpose of this section to induce you to infringe any patents or other property right claims or to contest validity of any such claims; this section has the sole purpose of protecting the integrity of the free software distribution system, which is implemented by public license practices. Many people have made generous contributions to the wide range of software distributed through that system in reliance on consistent application of that system; it is up to the author/donor to decide if he or she is willing to distribute software through any other system and a licensee cannot impose that choice.

This section is intended to make thoroughly clear what is believed to be a consequence of the rest of this License.

8. If the distribution and/or use of the Program is restricted in certain countries either by patents or by copyrighted interfaces, the original copyright holder who places the Program under this License may add an explicit geographical distribution limitation excluding those countries, so that distribution is permitted only in or among countries not thus excluded. In such case, this License incorporates the limitation as if written in the body of this License.

9. The Free Software Foundation may publish revised and/or new versions of the General Public License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns.

Each version is given a distinguishing version number. If the Program specifies a version number of this License which applies to it and "any later version", you have the option of following the terms and conditions either of that version or of any later version published by the Free Software Foundation. If the Program does not specify a version number of this License, you may choose any version ever published by the Free Software Foundation.

10. If you wish to incorporate parts of the Program into other free programs whose distribution conditions are different, write to the author to ask for permission. For software which is copyrighted by the Free Software Foundation, write to the Free Software Foundation; we sometimes make exceptions for this. Our decision will be guided by the two goals of preserving the free status of all derivatives of our free software and of promoting the sharing and reuse of software generally.

NO WARRANTY

11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.

12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.

END OF TERMS AND CONDITIONS


B.1.2. How to Apply These Terms to Your New Programs

If you develop a new program, and you want it to be of the greatest possible use to the public, the best way to achieve this is to make it free software which everyone can redistribute and change under these terms.

To do so, attach the following notices to the program. It is safest to attach them to the start of each source file to most effectively convey the exclusion of warranty; and each file should have at least the "copyright" line and a pointer to where the full notice is found.


one line to give the program's name and a brief idea of what it does.
Copyright (C) yyyy name of author

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

Also add information on how to contact you by electronic and paper mail.

If the program is interactive, make it output a short notice like this when it starts in an interactive mode:


Gnomovision version 69, Copyright (C) year name of author
Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
This is free software, and you are welcome to redistribute it
under certain conditions; type `show c' for details.

The hypothetical commands `show w' and `show c' should show the appropriate parts of the General Public License. Of course, the commands you use may be called something other than `show w' and `show c'; they could even be mouse-clicks or menu items--whatever suits your program.

You should also get your employer (if you work as a programmer) or your school, if any, to sign a "copyright disclaimer" for the program, if necessary. Here is a sample; alter the names:


Yoyodyne, Inc., hereby disclaims all copyright interest in the program
`Gnomovision' (which makes passes at compilers) written by James Hacker.

signature of Ty Coon, 1 April 1989
Ty Coon, President of Vice

This General Public License does not permit incorporating your program into proprietary programs. If your program is a subroutine library, you may consider it more useful to permit linking proprietary applications with the library. If this is what you want to do, use the GNU Library General Public License instead of this License.