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Attention, this script will delete /home/db2inst during create_instance option execution. Please always have backups and use it only for new installations. Please keeps your databases outside of /home/db2inst directory.

For DB2 v8.1 fp17a:

1) Download the latest fixpak corresponding to your architecture from:
ftp://ftp.software.ibm.com/ps/products/db2/fixes2/english-us/db2linux2632/
ftp://ftp.software.ibm.com/ps/products/db2/fixes2/english-us/db2linuxAMD64v8/
Untar downloaded file and make containing directory current.

2) Only deb distro: run attached rpm2deb.sh script in above directory.
On rpm distros skip this step.

3)On deb: dpkg -i *.deb
On rpm: rpm -i *.rpm

4) Run attached script:
/utils/db2/do.sh create_instance -s wse

5) Get IBM Java SDK at:
http://www.ibm.com/developerworks/java/jdk/linux/download.html 
or
https://www14.software.ibm.com/webapp/iwm/web/preLogin.do?source=lxdk
Move extracted IBMJava2-142 or IBMJava2-amd64-142 to /opt

Using above method I have successfully installed DB2 v8 fixpak 17a to Debian 32bit and Centos 64bit: db2linux2632/fixpak/FP17a_MI00283 and db2linux26AMD64/fixpak/FP17a_MI00286 respectively.

For DB2 v9.7 Express C:

1) Get your copy at: http://www-01.ibm.com/software/data/db2/express/download.html
untar it and run: db2_install

2) Run attached script:
/utils/db2/do.sh create_instance

More useful commands can be found inside do.sh script. If you have any questions please contact.

Several articles about manual DB2 installation are available on the internet:
http://project-tigershark.com/people/rob/blog/2007/01/02/installing-db2-91-on-ubuntu-dapper-606/
http://www.argon.org/~roderick/db2-linux-client.html
http://publib.boulder.ibm.com/infocenter/db2luw/v8/index.jsp?topic=/com.ibm.db2.udb.doc/start/t0007067.htm
http://www.liferay.com/web/guest/community/wiki/-/wiki/Main/DB2%20Express-C%209.5%20on%20CentOS%205.2
http://www.opennet.ru/base/dev/db2_linux.txt.html
http://linuxdocs.org/HOWTOs/DB2-HOWTO/