Hi everyone,

I'm about to migrate our DB2 on windows platform from V8 to V9. I have tested the migration on a test platform and everything was fine. My question is if I install V9 and migrate everything is there a way to fall back to V8 if needed? Can i have both V8 and V9 under one platform? If so, in order for me to fallback all i would have to do is drop the db2 instance and re create it back using the V8 binaries and restore the database from the V8 backups correct?

with v9 you can install differnt levels. but I don't think different verions
if this is possible, the indicated scenario would work

So if i need to fall back to V8 how would i do so?

You will need a db2look and db2move export fo the db in case you have to move back. If you update the instance, you cannot go back, but you can have both version 8 and 9 installed on the same Windows machine now (in Version 9). So if you install a new version 9 of DB2 and keep the old version, you could do a backup of V8 and restore to V9 instance. But your application connection info will change to access the version 9 database.

So i can have both versions on the same machine? So i'm assuming all i need to do it to install V9 in a different directory? Now if i needed to fallback and the instance has already been migrated couldn't i drop the instance and recreate it with the V8 binaires and then restore the db's from the V8 backups? This is the case if i needed to fallback to V8. Thanks again.

Not exactly.

If you install DB2 V9 to another directory, the database in V8 has not been migrated. It still exists in DB2 V8 instance.

Then after you have both V8 and V9 installed, you backup the V8 database and restore it on V9 instance. Then you have both databases working. If you don't like the V9 database, just keep using the V8 one, If the V9 database is OK, then drop the V8 one.

I would practise the above scenario, becasue it may actually be more complicated than a straight upgrade of an existing V8 DB2 install and database upgrade.

Note that it works a little different in Windows than it does in UNIX/Linux with regard to multiple versions of DB2 on the same machine.

Ok thank you. If i install V9 in the same directory as V8 it was overwrite everything with V9 biniaires. Once i run the V9 setup binaires will be installed and the instance will be migrated correct? Now in this situation if i wanted to fallback i would install the V8 binaires and it will overwrite the V9 bins correct? But the instance will still be V9 so i would drop the instance and create it in V8 correct? Thank again in advance

I don't know if you can install V8 on top of V9. Even if you could, you cannot de-migrate the instance or database from 9 to 8. You could do a db2look and db2move export before you migrate as a fall back option in case you need to recreate the database on V8 (after unistalling V9 and installing V8 again).

My suggestion was to run both V8 and V9 on the same machine. You would have two instances and each instance would have its own database. Obviously you need enough disk space for that option.

Couldn't i uninstall V9 and install V8? Drop the V9 instance and recreate the instance in V8 and then restore the databases? If i do decide to run both V8 and V9 would i create a new instance in V9 and then restore the V8 backups? I've heard that if you restore V8 backups in V9 Db2 will automatically migrate the V8 databases to V9? Thanks again

Hi rev1976,
Plz confirm if you followed the same procedure.....

Migration from version 8 to version 9:-
************************************

Tasks to be done before Migrating-

1) All the databases should be backed up in offline mode

2) The db2diagnostic information , instance configuration , and db configuration to be backed up

3) Backup all the db2 logs

4) Take a backup of all packages associted with the db.

5) Run the db2support utility to take a dump of all db and instance related information

6) Take a db2look on the db and save the output

After performing the above mentioned pre migration tasks the following tasks should be done-

1)We would need to check whether the db can be migrated , the following conditions must hold true for a db to be migrated-


-The database is not in an inconsistent state.
-The database is not in a backup pending state.
-The database is not in a restore pending state.
-The database is not in roll-forward pending state.
- The Table spaces are in a normal state.
-The database does not contain user-defined types (UDTs) with the name ARRAY, BINARY, DECFLOAT, VARBINARY and XML.
-The database does not contain the system-defined DATALINK data type.
-The database does not have orphan rows in system catalog tables that would cause database migration to fail.
-If SYSCATSPACE is a DMS table space and the automatic resizing functionality is not enabled, SYSCATSPACE has at least 50% free pages of total pages

this can be taken care of by running the "db2ckmig" command

2) db2 version 9 to be installed in a separate directory on the box.

3) Migrating the instance using "db2imigr" utility in the directory where db2 version 9 is installled ( need to login as root for this)

4) Migration of db2 administration server using "db2dasmigr" utilty ( need sysadm priv for this )

4) Migrating the database using the db2 migrate db command

Check the instance level and db after migrating that whether they have properly migrated to version 9 .

In environment with replication , the control tables will be migrated normally with the db only , but for consistent change data tables should be migrated manually , In our case we don't have CCD tables so , we can migrate without migrating the ccd tables to ccd tables of version 9

I would Highy recommend , taking an offline backup of the databases on both the zones before starting off with migration.

Both the zones will have to be migrated to same version.

IMPACT ON TABLES , INSTANCES , SQL PROCEDURES -

If the migration is successful , there should not be any impact on the data in tables , and instance configuration, But for sql procedures and functions , the instance must be migrated to same bit level i.e as now our instance on production is running on 32 bit environment so , if we migrate to version 9 , 64 bit environment , the sql procedures may not work there , they'll have to be dropped and created again.

IMPACT ON JAVA APPLICATIONS

For JDBC drivers of type 2, there should not be a problem to migrate but , they may cause support problems later on , so i would recommend migrating those applications to IBM data server drivers , For type 4 thin drivers migration we may have to consult a java expert.
Also , running of applications designed for 32 bit environment may not run properly on 64 bit environment , they must be linked to the correct 32 bit shared library path.

IMPACT ON SCRIPTS

Impact on scripts involving sql commands can only be established after they are run on the new environment , and should be rectified according to the anomalies they show there.

Cheers
Sandy

Thanks for the detailed procedure Sandy. Here's my procedure:

1) Take full offline backup of all databases
2) Save dbm cfg
3) Increase diaglevel and logfiles
4)Install V9 in same directory as V8 (this was done on our test system since we didn't have space to install it in another directory)
5) Run db2ckmig on each database to confirm that db is ready to be migrated
5) Migrate db's
6) Install fixpack (since windows will update the instance for you no need to run db2iupdt)
7) Connect and run bind commands on each database.

Question: I know it works on Linux platform but when you install V9 in a different directory all you need to do is execute db2imigr in the V9 dir to migrate the V8 instance over? But if I install V9 in the same directory as V8 hence overwriting V8 binaires the instance(s) will be migrated over automatically correct? Thanks again

i remember there is also a command to upgrade your catalog tables... missing its name.
After migration just have a look on sysibmadm views. i think they were added in V9. if they are present then its ok
or
maybe that command is only for fixpaks and not for version upgrade. need to check

When performing a "new install" b4 my migration will there be any problems when V9 is in a different directory to the application?

When intalling DB2 V9 in a different directory does it need to be installed under the same main path as V8? Ie V8 under f:\Program File\SQLLIB\ and i installed V9 under f:\Program Files\IBM\V9.1\

I may be wrong, but I thought for DB2 on Windows you don't have to specify a path of the install, even if you want to keep your old DB2 version. The install program can see if a previous DB2 version exists, and it asks you if you want to upgrade the previous version of DB2 already installed, or install a new version. It will figure out the paths for you (which is what I would recommend).