Huge Problem regarding Informix upgrade

[Gary Lee_7]

I have been assigned to a big project that involved hundreds of HP servers and Informix db.
The goal of the project areï¼
1. Port the applications on the HP-UX 10.20 to 11i
2. Migrate Informix 7.20 db to IDS9.4
3. Centralize the distributed Informix 7.20 dbs (For example: from 15 db systems to 1 db system)
Any suggestion regarding Informix migration solution will be appreciated.

Best regards

Ga

[Patrik Wolven]

Hi!

I have migrated from Informix 7.31 to 9.21. What I did is that I prepared the new machine, installed OS and configured Informix etc.

Then I exported the database in the old server and imported it in the new one. I used dbexport and dbimport.

If it's big databases the problem might be to move the export from the old servers to the new.

[Umapathy S]

Gary,
On the informix side, How do you plan to go.
Having many instances on a single machine, or many databases on a single instance.

Check out your performance requirements also.

Once you decide this then the migration wont be a big problem I believe.

HTH,
Umapathy

[Steve Lewis · Accepted solution]

Hi Gary,
I have done nearly this, in the past. If you want to run an upgrade, I would recommend first going to 7.31, then going to 9.2x, then 9.40.

If you dbexport/dbimport, then you may be able to read an 7.20 format dbexport file directly into 9.40 which would cut out a lot of time. You must set up your 9.40 database on a test system and try it. The format of the dbexport files has changed between 7.x and 9.x , but the new version may still be able to read the old format exports.

If you are going from XPS to a single instance, then good luck!

My biggest problem was migrating the apps to HP-UX 11.x from 10.20. A load of function calls vanished and some source code had to be re-written to enable native compilation. Sockets calls caused issues, since the calls changed from BSD to POSIX somewhere around 10.30, I think.

For tuning a 9.40 system, be aware that the database now goes through the physical log at a frightening rate, particularly in index builds. You will probably have to increase your physical log size.
If you are going to 64 bit, then you will find the logical log records get used up far more quickly than in the past, since every address is twice as long. The onstat commands change in output e.g. onstat -u will start printing 64 bit (8 byte) addresses. However you can still run 32 bit tools on a 64 bit engine. Big chunks cut down the admin required for a big instance. You will need big hardware and lots of memory to run it properly, just like you do with Oracle 9i. I hope you are going to a bigger server. Don't try to run this new config on anything less than an L class (no Ds, Rs, Ks or Ts). You will need a new cpu.
There is no shared memory connection (onipcshm) in 9.xx 64 bit and no dbcockpit. On the other hand, lots of other things are much better, such as HDR and I wouldn't want to go back.

[Gary Lee_7]

Hi, all

Thanks for your suggestions; they help to decide the method of Informix migration.
What Iâ m going to do is to use the multi-instances in a new HP rp-8400 with 8 875MHz CPU /16GB of memory and EMC disk array/1TB.
Thanks again

Gar