This HOWTO is intended for anyone interested in installing and using IBM DB2® Express-C 9 on a Linux® distribution. The goal is to include as many distributions as possible, on both 32–bit and 64–bit architectures, however both hardware and time resources are constrained, so if you come across a distribution/architecture combination that isn't covered in here or if you encounter a problem that isn't addressed, send a note to db2howto@gmail.com and I'll try to help verify or resolve your issue and add the information here.

The information found in this document is based on personal experiences installing and configuring IBM DB2 9 Express-C.

No liability for the contents of this document is accepted. Use the concepts, examples and information at your own risk. There may be errors and inaccuracies that could be damaging to your system. Proceed with caution, and, although it is highly unlikely that accidents will happen because of following advice or procedures described in this document, the author does not take any responsibility for any damage claimed to be caused by this document.

All copyrights are held by their by their respective owners, unless specifically noted otherwise. Use of a term in this document should not be regarded as affecting the validity of any trademark or service mark. Naming of particular products or brands should not be seen as endorsements.

This HOWTO is not official IBM documentation, and cannot be construed as such. IBM accepts no responsibility, liability or coverage for the material or instructions contained in this HOWTO. The views expressed in this document are those of the author, and not IBM Corporation.

Copyright (c) 2007 IBM Corporation.

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with the Invariant Sections being "Disclaimer" and "About the Authors". This document is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without ebaseven the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. A copy of the license is included in the section entitled "GNU Free Documentation License".

Ian Hakes is the current owner and maintainer of this HOWTO. Please send all suggestions for improvement, criticisms or questions to db2howto@gmail.com.

As always, big thanks to Dan Scott, who continues to be an invaluable resource to both myself and the open source community at large.

I'd also to thank: Rav Ahuja, Boris Bialek, Jason Chan, Ryan Chase, Irina Delidjakova, Leon Katsnelson, and Darin McBride for their support, input and patience while putting this document together.

Most of all, I must thank my wife and children for allowing me to spend weeknights and weekends on my laptop and test machines getting this document together. I couldn't have done it without their love and support.

Ian Hakes, has worked for IBM DB2 since 1999. Currently, he is involved in technical marketing for the DB2 Express-C product, developing technical documentation and evangelizing DB2 Express-C. Before that, he was the technical team lead for the DB2 Information Development department, and the writer responsible for the DB2 SQL Reference manual. His free time is spent mainly typing on computers, thinking about how much nicer it would be to watch a movie or to be sailing.

After downloading and extracting the tar.gz file, the file tree looks like this:

exp/ -|
    disk1/ -|
      db2_install    (* command line installation script *)
      db2setup       (* GUI installation launcher *)
      installFixPack (* not applicable for Express-C *)
      db2/ -|        (* installation and licensing files *)
      doc/ -|        (* install instructions and release notes *)

You can use three methods to install DB2:

Each method has its own advantages and disadvantages. The choice of method depends on your level of expertise and type of environment, but in general, if a graphical interface is available, using db2setup is recommended for ease of installation.

DB2 requires user IDs and groups for database authentication. This section discusses these IDs and groups and how to create them.

The installation on Red Hat Enterprise Linux 4 completed successfully, with no problems getting the GUI installer working, and no errors during the install. This smooth installation isn't surprising, given that RHEL 4 is an officially supported platform for DB2.

Basic test results (see Section 21, “Installation and operation test plan” for more details) were successful.

However, I found that after a reboot, the DB2 instance was not being restarted automatically, so clients could not connect to the database. To correct this problem, execute this command as the instance owner:

db2set DB2AUTOSTART=YES

This will ensure that the DB2 instance is initialized and ready to receive incoming connections after a reboot (intentional or otherwise).

Also, to allow DB2 access through the iptables-based firewall (which is enabled by default), it was necessary to modify the iptables firewall ruleset, which is kept in the /etc/sysconfig/iptables file. If you have enabled your firewall (using the iptables service), and you want to enable external connectivity to your DB2 server, you must open up TCP and UDP access to ports 523 and TCP access to any DB2 service ports. To make this work, add these rules to the iptablesfile (anywhere amongst the -j ACCEPT rules):

-A RH-Firewall-1-INPUT -p udp -m udp --dport 523 -j ACCEPT
-A RH-Firewall-1-INPUT -p tcp -m tcp --dport 523 -j ACCEPT
-A RH-Firewall-1-INPUT -p tcp -m tcp --dport 50000 -j ACCEPT

These rules were added directly to the iptables file to ensure that they persist in case of a system reboot. Note that you will need to add another new TCP rule to allow firewall access if you create any additional instances later.

You can use db2 get dbm cfg | grep SVCENAME to retrieve the service names and then check the /etc/services for the equivalent port values to open on your firewall.

The only installation error encountered was found when launching the ./db2setup command. The screen displayed this error:

ERROR:
    The following library files could not be loaded by db2langdir
    in /tmp/exp/disk1/db2/linux/install/../bin

        libstdc++.so.5
        libstdc++.so.5
        
    Check the following web site for the up-to-date system
    requirements of IBM DB2 Version 9.1:
        http://www.ibm.com/software/data/db2/udb/sysreqs.html

    Aborting the current installation ...

To resolve this error, use the yum package utility to install the necessary C++ compatibility libraries:

yum -y install compat-libstdc++-33

Installation succeeded after installing the C++ libraries.

Test results (see Section 21, “Installation and operation test plan” for more details) were successful, except the Configuration Assistant was very slow when launched from the DB2 Control Center. I eventually had to kill the process and it returned a DB2JAVIT : RC = 143 return code.

One strange effect encountered was that DB2 windows were not showing up when launching the Java-based GUI tools (and other windows were missing window decoration); however, logging off and then back in again solved the problem.

To inherit the DB2 instance environment from another home directory, create databases, dynamically load the DB2 libraries, and other tasks, I found that I had to either disable SELinux or modify the default SELinux policies. You can disable SELinux at run-time by running the following command as root:

# /usr/sbin/setenforce 0

Note that when you reboot SELinux will be enabled again. To disable SELinux permanently, edit /etc/selinux/config and set the following value:

SELINUX=disabled

If you have enabled your firewall (using the iptables service), and you want to enable external connectivity to your DB2 server, you must open up ports 523 and any DB2 service ports (use db2 get dbm cfg | grep SVCENAME to retrieve the service names and check /etc/services for the equivalent port values) in your firewall.

The only installation error encountered was found when launching the ./db2setup command. The screen displayed this error:

ERROR:
    The following library files could not be loaded by db2langdir
    in /tmp/exp/disk1/db2/linux/install/../bin

        libstdc++.so.5
        libstdc++.so.5
        
    Check the following web site for the up-to-date system
    requirements of IBM DB2 Version 9.1:
        http://www.ibm.com/software/data/db2/udb/sysreqs.html

    Aborting the current installation ...

To resolve this error, use the yum package utility to install the necessary C++ compatibility libraries:

yum -y install compat-libstdc++-33

Installation succeeded after installing the C++ libraries.

Basic test results (see Section 21, “Installation and operation test plan” for more details) were successful.

However, I found that after a reboot, the DB2 instance was not being restarted automatically, so clients could not connect to the database. To correct this problem, execute this command as the instance owner:

db2set DB2AUTOSTART=YES

This will ensure that the DB2 instance is initialized and ready to receive incoming connections after a reboot (intentional or otherwise).

Also, to allow DB2 access through the iptables-based firewall (which is enabled by default), it was necessary to modify the iptables firewall ruleset, which is kept in the /etc/sysconfig/iptables file. If you have enabled your firewall (using the iptables service), and you want to enable external connectivity to your DB2 server, you must open up TCP and UDP access to ports 523 and TCP access to any DB2 service ports. To make this work, add these rules to the iptablesfile (anywhere amongst the -j ACCEPT rules):

-A RH-Firewall-1-INPUT -p udp -m udp --dport 523 -j ACCEPT
-A RH-Firewall-1-INPUT -p tcp -m tcp --dport 523 -j ACCEPT
-A RH-Firewall-1-INPUT -p tcp -m tcp --dport 50000 -j ACCEPT

These rules were added directly to the iptables file to ensure that they persist in case of a system reboot. Note that you will need to add another new TCP rule to allow firewall access if you create any additional instances later.

You can use db2 get dbm cfg | grep SVCENAME to retrieve the service names and then check the /etc/services for the equivalent port values to open on your firewall.

The installation on OpenSUSE 10.2 completed successfully, with no problems getting the GUI installer working, and no errors during the install.

Basic test results (see Section 21, “Installation and operation test plan” for more details) were successful.

However, I found that after a reboot, the DB2 instance was not being restarted automatically, so clients could not connect to the database. To correct this problem, execute this command as the instance owner:

db2set DB2AUTOSTART=YES

This will ensure that the DB2 instance is initialized and ready to receive incoming connections after a reboot (intentional or otherwise).

Also, to allow DB2 access through the firewall (which is enabled by default), it was necessary to add the port values to the firewall using the YaST2 utility.

You can use the db2 get dbm cfg | grep SVCENAME command to retrieve the DB2 instance service name. By default, this is set as a TCP connection at port 50001. Note that you will need to add another new TCP rule to allow firewall access if you create any additional instances later. If you want to remotely administer the DB2 installation on this system, the UDP and TCP connections at port 523 should also be allowed through the firewall.

To open these ports using YaST, open the YaST tool, and select "Security and Users, then select the "Firewall" icon. In the Allowed Services setup panel, click on the "Advanced" button. In the TCP ports dialog, add 523 50001, and in the UDP ports dialog, add 523. Click "Next" until the setup wizard completes and restarts the firewall. Remote connections will now pass through to the DB2 instance.

The installation on SLES 9 completed successfully, with no problems getting the GUI installer working, and no errors during the install. This smooth installation isn't surprising, given that SLES 9 is an officially supported platform for DB2.

Basic test results (see Section 21, “Installation and operation test plan” for more details) were successful.

However, I found that after a reboot, the DB2 instance was not being restarted automatically, so clients could not connect to the database. To correct this problem, execute this command as the instance owner:

db2set DB2AUTOSTART=YES

This will ensure that the DB2 instance is initialized and ready to receive incoming connections after a reboot (intentional or otherwise).

Also, to allow DB2 access through the firewall (which is enabled by default), it was necessary to add the port values to the firewall using the YaST utility.

You can use the db2 get dbm cfg | grep SVCENAME command to retrieve the DB2 instance service name. By default, this is set as a TCP connection at port 50001. Note that you will need to add another new TCP rule to allow firewall access if you create any additional instances later. If you want to remotely administer the DB2 installation on this system, the UDP and TCP connections at port 523 should also be allowed through the firewall.

To open these ports using YaST, open the YaST tool, and select "Security and Users, then select the "Firewall" icon. In the setup panel, click "Next" and then on the "Expert button. In the ports dialog, add 523 50001. Click "Next" until the setup wizard completes and then "Continue" so that YaST will restart the firewall with the new configuration. Remote connections will now pass through to the DB2 instance.

The installation on SLES 10 completed successfully, with no problems getting the GUI installer working, and no errors during the install. This smooth installation isn't surprising, given that SLES 10 is an officially supported platform for DB2.

Basic test results (see Section 21, “Installation and operation test plan” for more details) were successful.

However, I found that after a reboot, the DB2 instance was not being restarted automatically, so clients could not connect to the database. To correct this problem, execute this command as the instance owner:

db2set DB2AUTOSTART=YES

This will ensure that the DB2 instance is initialized and ready to receive incoming connections after a reboot (intentional or otherwise).

Also, to allow DB2 access through the firewall (which is enabled by default), it was necessary to add the port values to the firewall using the YaST2 utility.

You can use the db2 get dbm cfg | grep SVCENAME command to retrieve the DB2 instance service name. By default, this is set as a TCP connection at port 50001. Note that you will need to add another new TCP rule to allow firewall access if you create any additional instances later. If you want to remotely administer the DB2 installation on this system, the UDP and TCP connections at port 523 should also be allowed through the firewall.

To open these ports using YaST, open the YaST tool, and select "Security and Users, then select the "Firewall" icon. In the Allowed Services setup panel, click on the "Advanced" button. In the TCP ports dialog, add 523 50001, and in the UDP ports dialog, add 523. Click "Next" until the setup wizard completes and restarts the firewall. Remote connections will now pass through to the DB2 instance.

The installation on SLED 10 completed successfully, with no problems getting the GUI installer working, and no errors during the install.

Basic test results (see Section 21, “Installation and operation test plan” for more details) were successful.

However, I found that after a reboot, the DB2 instance was not being restarted automatically, so clients could not connect to the database. To correct this problem, execute this command as the instance owner:

db2set DB2AUTOSTART=YES

This will ensure that the DB2 instance is initialized and ready to receive incoming connections after a reboot (intentional or otherwise).

Also, to allow DB2 access through the firewall (which is enabled by default), it was necessary to add the port values to the firewall using the YaST2 utility.

You can use the db2 get dbm cfg | grep SVCENAME command to retrieve the DB2 instance service name. By default, this is set as a TCP connection at port 50001. Note that you will need to add another new TCP rule to allow firewall access if you create any additional instances later. If you want to remotely administer the DB2 installation on this system, the UDP and TCP connections at port 523 should also be allowed through the firewall.

To open these ports using YaST, open the YaST tool, and select "Security and Users, then select the "Firewall" icon. In the Allowed Services setup panel, click on the "Advanced" button. In the TCP ports dialog, add 523 50001, and in the UDP ports dialog, add 523. Click "OK" and then "Next" until the setup wizard completes and restarts the firewall. Remote connections will now pass through to the DB2 instance.

Note that root logins are not allowed in Mandriva, so you will need to log on as another user, then run the su -l command from a terminal session to gain root access before you launch the ./db2setup command.

The only installation error encountered was found when launching the ./db2setup command. The screen displayed this error:

ERROR:
    The following library files could not be loaded by db2langdir
    in /tmp/exp/disk1/db2/linux/install/../bin

        libstdc++.so.5
        libstdc++.so.5
        
    Check the following web site for the up-to-date system
    requirements of IBM DB2 Version 9.1:
        http://www.ibm.com/software/data/db2/udb/sysreqs.html

    Aborting the current installation ...

To resolve this error, use the drakrpm package utility to install the necessary C++ compatibility libraries:

libstdc++5-3.3.6-3mdk
libstdc++6-4.1.1-3mdk

Installation succeeded after installing the C++ libraries.

Basic test results (see Section 21, “Installation and operation test plan” for more details) were successful.

However, I found that after a reboot, the DB2 instance was not being restarted automatically, so clients could not connect to the database. To correct this problem, execute this command as the instance owner:

db2set DB2AUTOSTART=YES

This will ensure that the DB2 instance is initialized and ready to receive incoming connections after a reboot (intentional or otherwise).

Also, to allow DB2 access through the firewall (which is enabled by default), it was necessary to modify the add in the appropriate firewall ports. To enable external connectivity to your DB2 server, you must open up TCP and UDP access to ports 523 and TCP access to the DB2 instance port (50001 by default).

Open the Mandriva Control Center, choose the Security tab, and then the "Set up a personal firewall..." icon. In the firewall setup panel, click the "Advanced button and add 523/udp 523/tcp 50001/tcp to the Other ports text box. Click "OK until the firewall setup is complete.

Note that you will need to add another new TCP rule to allow firewall access if you create any additional instances later.

Since you cannot log in as root directly with an Ubuntu system, this DB2 installation is run as the default user created during Ubuntu setup (i.e. the regular user account with 'sudo' capability).

There are two ways of installing DB2 Express-C 9 on Ubuntu. The harder of the two methods is to use the default DB2 db2setup, and then make adjustments to the Ubuntu system afterwards to handle the slight differences of Ubuntu's Debian-based packaging system. For reasons of clarity and brevity, I will omit the instructions for doing it this more difficult way; however, if you would like to see these instructions, please send me an email (db2howto@gmail.com) and I will pass them along.

The easy way to install DB2 Express-C on Ubuntu 6.06 LTS is to use the Synaptic package installer, and almost everything is done for you, from downloading to installation and configuration. Here's how to do it:

After hitting the "Apply" button, Synaptic will download the DB2 Express-C package, along with a few dependent libraries, then unpack and install the package and finally configure the DB2 users and default instance.

After installation by Synaptic, there are a few steps required to get DB2 up and running smoothly.

Since you cannot log in as root directly with an Ubuntu system, this DB2 installation is run as the default user created during Ubuntu setup (i.e. the regular user account with 'sudo' capability).

There are two ways of installing DB2 Express-C 9 on Ubuntu. The harder of the two methods is to use the default DB2 db2setup, and then make adjustments to the Ubuntu system afterwards to handle the slight differences of Ubuntu's Debian-based packaging system. For reasons of clarity and brevity, I will omit the instructions for doing it this more difficult way; however, if you would like to see these instructions, please send me an email (db2howto@gmail.com) and I will pass them along.

The easy way to install DB2 Express-C on Ubuntu 7.04 is to download the DB2 Express-C Debian package file and then use the Ubuntu package installer. This way, almost everything is done for you, from installation to configuration. Here's how to do it:

After hitting the "Install Package" button, the Ubuntu package installer will unpack and install the package and configure the DB2 users and default instance. Click the "Close" button once the installation is complete.

After installation by Synaptic, there are a few steps required to get DB2 up and running smoothly.

No problems were encountered during the default installation.

After installation, I could not create the SAMPLE database, or any database for that matter. DB2 returned this strange error:

SQL0440N No authorized routine named RTRIM of
type "FUNCTION" having compatible arguments was found

I then rebooted and logged back in as root, then opened a terminal session:

su - db2inst1
db2sampl

and then SAMPLE database creation worked as expected. After this, I logged out as root, then back in as db2inst1 and all DB2 tests completed successfully.

If you want to enable external connectivity to your DB2 server, you must open up ports 523 and any DB2 instance services (use db2 get dbm cfg | grep SVCENAME to retrieve the service names and check /etc/services for the equivalent port values) in your firewall.

To begin, mount the DB2 Information Center CD in your system drive, or if you downloaded the compressed file through the Express-C website, expand the tarball containing the installation utilities.

Change to the base directory (doce/disk1/) and run the db2setup utility. This will launch the DB2 setup wizard. You can also use the other setup methods, but since the GUI installation sets up and configures everything for you, it's the method I recommend.

Installation Steps:

/etc/init.d/db2icdv9 restart

The Information Center daemon is set up during installation and is used to launch the background process that runs the Information Center. The daemon script, named db2icdv9 is installed to the /etc/init.d/ directory, and start up symbolic links are added to the /etc/init.d/rc.X/ run-level folders. By default, the daemon is turned on for run-levels 3 and 5. You can modify these run-levels with any system init utility (chkconfig, ntsysv, or any of the X-based variants).

There are 5 commands you can pass to the daemon:

There are three possible methods to access the DB2 Information Center:

You can configure which access method will be used, either during the DB2 installation (only by specifying a "Custom" installation), or afterwards in the tools configuration panel (in the GUI tools), or from the command line.

To make the change using the GUI tools (Control Center), open the Tools menu, select Tools Settings, and then the Documentation tab. On this panel, you can specify a host URL and port where an Information Center can be found. When putting a hostname in, do not add the "http://" prefix, or any subdirectories – just type in the hostname, and the internal code will do the rest.

To change the access points from the command line, execute these commands:

db2set DB2_DOCHOST=host_URL
db2set DB2_DOCPORT=host_port

where host_URL is the location hostname of the Information Center. This could be: mydocserver.myorg.net or localhost (for a local installation), and host_port is the port number where the Information Center was installed.

By default, these DB2 environment settings are blank, which means that DB2 defaults to the http://publib.boulder.ibm.com/infocenter/db2help/ Web site.

To invoke the DB2 Information Center from the GUI tools, click on the "?" icon in the toolbar, any of the "Help" hyperlinks or buttons, or by selecting any of the menu items in the "Help" menu.

To invoke the DB2 Information Center from the command line, issue any of these commands:

To start the DB2 Control Center:

The left side of the DB2 Control Center provides an object based 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 the object to bring up a context menu.

As mentioned above, the new DB2 Information Center is a revamped documentation display system that now encapsulates the task, concept and reference information required to properly run DB2 . It can be installed locally, on an intranet server, or accessed directly from the ibm.com hosting service.

To start the DB2 Information Center:

Alternatively, you can launch the Information Center from within the Control Center (or any of the other GUI tools), by clicking an item under the "Help" menu, or by clicking on the "?" (question mark) icon.

If you did not install the DB2 Information Center, or have not configured your tools to use a different server, then these commands will launch a detected browser, and take you directly to the IBM hosted DB2 Information Center at http://publib.boulder.ibm.com/infocenter/db2help/.

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 DB2 sample database. 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 from the DB2 First Steps launchpad, or by issuing the db2sampl command from the command line.

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

db2 CONNECT TO database USER userID USING password

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

db2 CONNECT TO database USER userID

To connect to a database using the default user ID, issue the command:

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 rows from the EMPLOYEE table in the SAMPLE database, issue this command:

db2 "SELECT * FROM employee"

You can avoid typing db2 as the prefix for every SQL statement and DB2 command by issuing DB2 commands using the Command Line Processor (CLP). To start the CLP, issue the db2 command by itself from a Linux command line terminal. 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 =>

Some users prefer to avoid the CLP because it prevents using the command line history features of the shell.

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, but your mileage may vary.

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