Comment 0 for bug 189538

If you have already installed DB2 Version 9.0 and upgrade to Version 9.5 you will encounter some problems with your existing installation:

Reason: 9.5 is a full point release, not just a fixpack. This differs from previous Versions of DB2 (e.g. Versions 7 and 8). Migration of existing Data is needed.

What happens?

1. The existing instance "db2inst1" created during the installation of 9.0 will stop operating. All symbolic links in ~db2inst1/sqllib are inoperative as the target directory "/opt/ibm/db2/V9.0/ is removed by the update.

2. A new instance (user) "db2inst2" is created by the script. This instance is fully operational.

I find this behaviour kind of critical as running production databases might be affected.

The following workaround can help with getting the instance db2inst1 up and running again:

# kill all processes of user db2inst1 or reboot first
# then

su - db2inst1
rm -rf sqllib
exit
sudo /opt/ibm/db2/V9.5/instance/db2icrt -u db2inst1 db2inst1
su - db2inst1
#
db2 update dbm cfg using svcename <portname>
db2start
db2 catalog database sample (repeat for other datbases)
db2 migrate database sample

Another way to recover would be restoring a previous backup image to the newly created instance.

I would highly recommend to change the update skript in respect of this changed db2 behaviour. 9.0 will be supported with separate Fixpacks by IBM. However, 9.5 offers really great new features and would be my recommended choice over 9.0. A working upgrade/migration script should be feasible. Youre welcome to get back to me if I can be of any help.