Revision History | ||
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Revision 0.7 | May 26, 2000 | Revised 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. | ||
Revision 1.0 | July 6, 2000 | Revised by: dbs |
Added basic Debian instructions. Corrected some factual, stylistic, and grammatical mistakes. Licensed document under GNU GPL. Submitted document to LDP. |
This HOWTO gives you explicit instructions on installing DB2 Universal Database Version 7.1 for Linux on the following Intel x86-based distributions: Caldera OpenLinux 2.4, Debian, Red Hat Linux 6.2, SuSE Linux 6.2 and 6.3, and TurboLinux 6.0. After installing DB2, you can work with a sample database, connect to your DB2 server from a remote machine, and administer DB2 using the DB2 Control Center.
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.
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 supports are:
Caldera OpenLinux 2.4
Red Hat Linux 6.2
SuSE Linux 6.2 and 6.3
TurboLinux 6.0
For Debian, I have included very basic installation instructions 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 plan to install DB2 Version 6.1 on Linux, I'll try to track down some references for you, but I don't include any DB2 Version 6.1 information here. 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.
I like my friends at the Linux Documentation Project, so you'll always be able to find the most up-to-date version of this document at the LDP web site.
Copyright (c) 2000 International Business Machines Incorporated.
This document is free documentation; 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 document 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 document; if not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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 <daniels@REMca.ibm.com> (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.
Dan Scott has been employed by IBM Canada as an Information Developer since 1998—approximately when DB2 was first ported to Linux. It's probably just coincidence. He has documented and tested DB2 application development for the bulk of that time. In his spare time he can occasionally be found mourning for his dearly departed motorcycle, abusing his body on his mountain bike, or contemplating how to upgrade his Linux distribution at home (which started life as Mandrake 5.3 and has mutated wildly ever since) without suffering the wrath of his girlfriend.
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
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.
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.
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
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.
2.2.12 or greater. I've upgraded to 2.2.15 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.
2.9.0. This exact version is mandatory.
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.
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.
The IBM Developer Kit for Java 1.1.8 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 is the March 22, 2000 release. You can get the IBM Developer Kit and Runtime Environment for Linux, Java Technology Edition, Version 1.1.8, at the IBM Java Developer Kit downloads web site.
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.
DB2 calls the netscape command when you:
display the online help for the DB2 Control Center
display information using the DB2 Information Center
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 |
Table 1. Prequisite levels, by distribution
Package | Caldera OpenLinux 2.4 | Red Hat 6.2 | SuSE 6.2 | SuSE 6.3 | TurboLinux 6.0 |
---|---|---|---|---|---|
glibc | 2.1.2 | 2.1.2 | 2.1.1 | 2.1.2 | 2.1.2 |
Linux kernel | 2.2.14 | 2.2.14 | 2.2.10 | 2.2.13 | 2.2.13 |
libstdc++ | 2.9.0 | 2.9.0 | 2.9.0 | 2.9.0 | 2.9.0 |
pdksh | 5.2.14 | 5.2.14 | 5.2.14 | 5.2.14 | 5.2.14 |
This section contains instructions that you must follow before installing DB2.
Preparing for the installation of DB2
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 |
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 |
Install the IBM Developer Kit for Java. A brief set of installation directions is included in Section 10.
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 ) |
Follow the instructions in Section 4 the generic section on installing DB2, and go ahead and create the instances. It's probably a good idea at this point to read through Section 3.1.3 to keep in mind the steps that you need to take after installing DB2.
It means something went slightly wrong, but it's okay. You may get this message splashed across your installation screen one or more times during the DB2 installation process, but other than not looking pretty, DB2 still installs correctly. Caldera apparently doesn't include a /etc/login.defs configuration file. The file controls the default options for the useradd command for adding new users, including policies like how many days before the new user's password expires and whether a home directory should be created for a new user. For more information on the /etc/login.defs file, refer to the man page for useradd.
This section contains instructions that you must follow after installing DB2.
The most important step is to manually add the instance user ID to the corresponding instance group you defined during the instance creation step. DB2 and Caldera OpenLinux don't get this part of the DB2 instance creation process right, so you have to do it yourself. You can add an instance user ID to an instance group in two ways:
Edit /etc/group to add the appropriate instance user ID to the last field for each group.
Use the COAS utility to manage your groups by selecting KDE menu, Settings, COAS, System, Accounts, then selecting the Groups submenu and the Manage Groups menu item.
The DB2 Control Center and the DB2 Information Center use the Netscape browser to display help and documentation. This works for the first document you display in the browser, but if you try to switch to a different DB2 document (for example, from one book to another), you may instead be redirected to the default home page set by the Caldera OpenLinux installation process. I found that this problem went away as soon as I changed the default home page in the Edit menu, Preferences menu item.
Add a file called .hushlogin to the home directory of each of your instance user IDs. This should prevent the Welcome to your OpenLinux system! messages while running DB2 commands.
DB2 generates these messages on Caldera because the DB2 commands run under the root user ID, which in turn becomes the instance owner to invoke commands. Part of this su process calls one or both of /etc/config.d/shells/csh.login and /etc/config.d/shells/profile, which in turn call the /etc/config.d/shells/OL-greeting script that contains the offensive string.
Instead of adding .hushlogin to every user's home directory, you could probably edit /etc/config.d/shells/OL-greeting to remove the message (or change it to something else, if you want). I haven't tried it myself, so let me know what works best.
Preparing for the installation of DB2
Install the pdksh-5.2.14-2.i386.rpm package from the Red Hat CD-ROM 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-5.2.14-2.i386.rpm |
Follow the instructions in Section 4, the generic section on installing DB2 and creating instances.
With Red Hat 6.2, you don't need to take any special steps after installing DB2 Version 7.1. It works.
SuSE 6.3 includes all of the required packages at or above the minimum required levels for DB2 Version 7.1. If you have a choice between installing SuSE 6.3 or 6.2, I would strongly recommend installing 6.3.
SuSE 6.2, ships with a glibc level of 2.1.1 and a kernel level of 2.2.10; however, in my tests this did not cause any problems with installation, running the DB2 Control Center, or creating and running Java and C applications for DB2.
Follow the instructions in Section 4, the generic section on installing DB2. When you create the instances, keep in mind the following information about creating instances on SuSE.
The default installation packages in the SuSE distribution include an old beta version of DB2. This means that the default DB2 user IDs and groups used by the Create Instance menu are already created when you try to create an instance for DB2 Version 7.1, causing the following problems:
Default user name already exists
Because the default user name already exists, 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.
Default group name already exists
Because the default group name already exists, 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.
Default home directory points to /usr/lib/db2/
Because the default user name already exists and was created in the /usr/lib/db2/ directory, you have to manually specify the location of the new instance. The default home directory is /home/.
With SuSE 6.2 or above, I have not needed to take any special steps after installing DB2 Version 7.1. It just works—and that's nice.
TurboLinux 6.0 includes all of the required packages at or above the minimum required levels for DB2 Version 7.1.
Follow the instructions in Section 4, the generic section on installing DB2.
When you run the DB2 Control Center with TurboLinux 6.0, the console window may display a number of map failed messages. These messages do not indicate a serious problem, so do not worry about them.
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.
You'll find the following executables on the root directory of the DB2 Version 7.1 installation CD-ROM:
db2setup: Use the db2setup command to install DB2 Version 7.1, to create or modify DB2 instances, and to create a DB2 Administration Server. Once you install DB2, db2setup is copied to the /usr/IBMdb2/V7.1/install directory to enable you to create or modify instances without the CD-ROM.
db2_install: The db2_install command provides an alternate means of installing DB2 RPMs. Unlike db2setup, it does not enable you to create a DB2 instance or Administration Server, or install a license key. I highly recommend db2setup.
db2_deinstall: Use the db2_deinstall command to uninstall the DB2 Version 7.1 packages on your system. For more information, see Section 7.
Note: The db2setup command provides a terminal-based text menu for your installation and instance creation options. Unfortunately, db2setup on Linux sometimes encounters a few formatting bugs in terminal emulators. Running db2setup from the TTY console works well. Within an X session, the rxvt or xterm terminals work quite well, but gnome-terminal is rather frustrating to use. If the text menu formats incorrectly, press CTRL-L to refresh the menu.
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
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.
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.
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.
Options for DB2 servers
This option enables your DB2 server to replicate data to other DB2 servers, and, with additional software, across non-DB2 servers as well. This option requires about 5 MB of disk space.
This option enables your DB2 server to participate in a join with data from other database servers. This option requires about 2 MB of disk space.
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.
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.
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).
Susan Williams reported success in installing DB2 Version 7.1 on Debian using the following script as root:
Example 1. Installation script for DB2 Version 7.1 on Debian
#!/bin/bash cd / for f in /mnt/cdrom1/db2/*rpm do alien -d -i -c $f done |
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.
Using this approach 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.
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:
creates one or more new user IDs and corresponding home directories
creates a subdirectory in the instance home directory called sqllib
alters the .bashrc file to call the ~/sqllib/db2profile shell script to set up the environment for the instance
Like a queen bee in a hive, only one DB2 Administration Server can exist on any given DB2 server. By locally or remotely logging as the user ID that corresponds to the DB2 Administration Server, a database administrator uses the DB2 Administration Server to create, drop, or change the properties of DB2 instances.
To quote the IBM DB2 Universal Database Version 7.1 Administration Guide definition of an instance:
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.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).
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.
Issue the db2setup command as described in Section 4.2.
Select [ Create... ].
Select the check box for Create the Administration Server. The Administration Server window is displayed.
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.
Select the Use default UID check box. As far as I can tell, this setting is always right.
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.
Select the Use default GID check box. Again, as far as I can tell, this setting is always right.
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/. |
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.
Issue the db2setup command as described in Section 4.2.
Select [ Create... ].
Select the Create a DB2 Instance check box. The DB2 Instance window is displayed.
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.
Select the Use default UID check box. As far as I can tell, this setting is always right.
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.
Select the Use default GID check box. Again, as far as I can tell, this setting is always right.
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/. |
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. |
Select [ Properties... ] to change the properties for the instance.
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.
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.
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.
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.
Select [ OK ] to create the fenced user.
To remove DB2 from your workstation cleanly, perform the following steps:
Log in as root.
List all DB2 instances:
bash# /usr/IBMdb2/V7.1/instance/db2ilist |
Drop each instance listed in the previous step with the following command:
bash# /usr/ibmdb2/v7.1/instance/db2idrop instance-name |
Drop the DB2 administration server:
bash# /usr/IBMdb2/V7.1/instance/dasidrop `/usr/IBMdb2/V7.1/instance/dasilist` |
Uninstall all of the DB2 packages on your system using the db2deinstall command on your DB2 CD-ROM:
bash# /mnt/cdrom/db2/db2_deinstall -n |
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 10.
The left side of the DB2 Control Center provides an object-oriented view of the database objects that you have catalogued, including DB2 instances and databases on other DB2 servers. One way to add, edit, or drop database objects is to right-click on an object to bring up a menu.
To start the DB2 Control Center
Ensure you are logged on to your Linux workstation using either the DB2 Administration Server user ID or the DB2 instance user ID. If you use the su command to become the user, ensure you include the -l parameter to initialize the environment for the user.
Start the X server, if it is not already started.
Issue the db2cc command to start the DB2 Control Center. Depending on the speed of your system, it may take a few seconds for the splash screen to appear, and longer before the full DB2 Control Center appears.
The DB2 Information Center provides tree views of the information about DB2 that is installed on your system, as well as a number of links to web sites with further information. If you did not install the DB2 documentation, the tree views contain fewer links.
To start the DB2 Information Center
Ensure you are logged on to your Linux workstation using either the DB2 Administration Server user ID or the DB2 instance user ID. If you use the su command to become the user, ensure you include the -l parameter to initialize the environment for the user.
Ensure that the X server is started.
Issue the db2ic command to start the DB2 Information Center. Depending on the speed of your system, it may take a few seconds for the splash screen to appear, and longer before the full DB2 Information Center appears.
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:
db2 CONNECT TO database USER userID USING password
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:
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.
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 =>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.
The following section covers some of the common problems you may encounter while installing DB2, creating an instance, or using a DB2 database.
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".
DB2 issues this error when it can't find the pdksh or ksh shells. This has probably occurred because you did not install the pdksh package for your distribution. See Section 3 for more details on installing the pdksh package for your Linux distribution.
9.1.2. After creating a DB2 instance, I installed the Application Development Client, but I can't use that instance to create DB2 applications.
When you add the Application Development Client after you initially install DB2 and create a DB2 instance, your existing DB2 instance won't recognize the db2 prep command. Instead, DB2 returns the following error: DB21051E The command is not supported for this environment.
The problem is that when you install a new DB2 component, DB2 does not automatically update existing DB2 instances to include links to the new libraries and executables. To update an existing DB2 instance, use the db2iupdt command as root:
bash# /usr/IBMdb2/V7.1/instance/db2iupdt instance-name |
bash# /usr/IBMdb2/V7.1/instance/db2iupdt -e |
The following section covers some of the common problems you may encounter when you create a DB2 instance.
DB2 often fails to create an instance because you became root by issuing the command bash$ su root rather than bash$ su -l root, which uses the environment settings for the root account. Check the contents of the DB2 install log in /tmp/db2setup.log. If the installer has issued the following error message:
DBI1517E An attempt to execute a command in a subprocess failed. Explanation: An error was detected when attempting to execute a command in a subprocess. One of the following problems occurred: o The command does not exist. o Incomplete command search path. o Incorrect access permissions on the command. o System resource problem. |
PATH is normally set correctly for you if you log in as root, or issue the command bash$ su -l root to become root. You can add /usr/sbin to the PATH environment variable by issuing the following command at the terminal prompt, or including it in /root/.bashrc:
export PATH=$PATH:/usr/sbin |
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).
This is one area where DB2 and Caldera OpenLinux don't work well together. Fix this by manually adding each instance user ID to the group you defined during instance creation. Here's the full help from the IBM DB2 Message Reference:
DBI1766W Cannot change the secondary group list of "". Explanation: A code, "", is returned when attempting to change the secondary group list of the given user ID. One of the following situations has occurred: o NIS is running. o One or more processes are currently being executed under the given user ID. User Response: You must add the group ID, "", to the secondary group list of the user ID, "", so that the Adminstration Server can function properly. o If there happens to be any process run under the given user ID, terminate all of these processes and follow the instructions above to setup the secondary group list of this user ID. o If you are running this command on an NIS client, try the above instructions to setup the secondary group list of this user ID on your NIS server. |
The following section covers some of the common problems you may encounter when you use a DB2 database.
The number of connections that DB2 can support depends on two #define variables included in the kernel source header files.
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. Thankfully, the stock kernels shipped with the Red Hat 6.1, Red Hat 6.2, SuSE 6.2, SuSE 6.3, and TurboLinux 6.0 distributions set the value of NR_TASKS to 2560, thus allowing 1280 connections for a single DB2 instance. However, Caldera OpenLinux 2.4 ships with a kernel in which NR_TASKS is set to the default value of 512. Caldera users may want to consider recompiling the kernel.
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.
Note: To be added: the value of this variable in the stock kernels shipped with the Caldera OpenLinux 2.4, Red Hat 6.2, SuSE 6.2, SuSE 6.3, and TurboLinux 6.0 distributions.
9.3.2. When I start the DB2 Control Center, I get a message box with the error SQL1042C An unexpected system error occurred.
This error occurs only the first time you start the Control Center. Note that the message box may be mostly covered up by the pretty DB2 splash screen; if this is the case, you have to move the error message window down and press the "Close" button. The Control Center then starts correctly, and you should not get the error message again.
If the Control Center displays an empty "Systems" folder, you might need to catalog the DB2 Administration Server manually for the local instance from which you are trying to run the Control Center. This assumes that you have created the DB2 Administration Server instance before starting the Control Center.
To catalog the DB2 Administration Server, issue the following command:
bash$ db2 catalog admin local node machine-name instance Administration-Server-name system machine-name ostype linux |
9.3.4. When I try to start the DB2 Control Center with the db2cc command, the splash screen comes up, then disappears.
On Caldera, the Control Center didn't work for me until I added the instance user IDs to the appropriate groups. For more information, see Section 3.1.3.1.
Ensure that you have installed the IBM Developer Kit for Java 1.1.8, and that the /usr/jdk118/bin directory is in your path. If you issue the command
bash$ java -fullversion |
9.3.5. 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)
Caldera OpenLinux includes this annoying message as part of their default login. For instructions on how to remove or modify this output, see Section 3.1.3.3.
This section gives you quick and dirty instructions on how to install the IBM Developer Kit for Java, version 1.1.8. You need this version 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, and even later versions of the IBM Developer Kit for Java, such as JDK 1.3.x, are not supported. |
Installing the IBM Developer Kit for Java
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.
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 |
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.
Following is a list of references to further information on using DB2 V7.1 for Linux:
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.
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.
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.
This web site contains the latest information about restrictions, workarounds, or additional documentation for developing applications with DB2.
This web site contains general information about using DB2 for Linux, including a link to the free download of DB2 Personal Developers Edition.
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.
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.
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.
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.
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.
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The precise terms and conditions for copying, distribution and modification follow.
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".
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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.
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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.
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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.
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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.
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NO WARRANTY
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END OF TERMS AND CONDITIONS
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.