Hi Ryzor,

Everyone is correct - you can't upgrade directly from 4.x to 6.x. You have to bounce from 4.x to 5 and then to 6.

If you consult the Interactive Upgrade Guide and put in your versions, it will tell you the upgrade process, but while upgrading from 4 - 6 is a bit tricky, there are no problems as such. The main thing is that in the later 4.x versions the RM application was split from the JTS and made into a stand alone app. This means that when you upgrade from 4 - 5 you will need to perform an extra step of backing up the JTS database and restoring it into an new RM database, and then perform some operations that remove the duplicate tables (so remove the RM tables from JTS, and the JTS tables from RM).

Another thing is that the default app server changed from Tomcat to Liberty, and depending on what app server you are currently on I would move to Liberty - this will require you to double check your app server settings and possibly migrate your LDAP or user directory settings by hand.

The only other thing is that in later 4.x versions there were some significant changes in QM that required a lot of database updates, and these can take a VERY long time if you have a big database. Fortunately, at the same time they introduced an online upgrade process where the bulk of the upgrade in QM could be done as a pre step while your old installation was still running. This greatly reduced the upgrade down time for QM.

I have performed a half dozen 4 - 6 upgrades, and they are fiddly but not difficult. I would:
- practice in a sandbox if you can first
- apply the very latest 4.x iFix for your release, or upgrade to the 4.x release (latest iFix) recommended by the Interactive Install
- always install the latest 5.x and 6.x releases and patch them to the latest iFix before performing the upgrade
- make sure your 5.x intermediate step works correctly before moving to the 6.x step
- snapshot your database and index directories before starting the actual upgrade, and also at the 5.x version level, so you can roll back half way if necessary.
- make sure your database stats are up to date at each level before doing the upgrade

I think you won't be able to directly upgrade from 4.0.0 to 6.0.4. You may need to upgrade to any intermediate level in version 5.0.x first and then to 6.0.4. Please generate an interactive upgrade guide, as per your current environment and go through all the pre-upgrade steps.

https://www.ibm.com/support/knowledgecenter/en/SSYMRC_6.0.4/com.ibm.jazz.install.doc/topics/interactive_guides.html