Re: Migration from 8.1.5 to 9.2 RAC

Hi
I believe that export/import is the best method to migrate from a single instance to a parallel server setup. Before import you need to create all application objects with the necessary freelists/freelist groups for tables/indexes. You need to have separate set of rollback segments for each instance. You need to configure gc* parameters for each datafile in the database based on the transactions that would afffect them. Mere moving of physical files to raw devices is not a good idea. You should have a separate raw slice for each datafile and hence plan it accordingly for future growth. Also take into account your controlfile growth if using rman as you would be creating raw files for all except archived logs. I have done this exercise while migrating from HP single instance to IBM parallel server setup on 8.1.6.3.
Hope this helps.

Cheers,
Ashok

Candido Dessanti <termy_at_blunet.it> wrote in message news:<3D80BE7A.5000100_at_blunet.it>...
> > Sorry, I did not understand that. After upgrading 8.1.5 to 8.1.7 I
 have a
> > single instance 8.1.7
> > database. And I have no a 9.2 RAC database at this moment. Should I
 install
> > a starter 9.2 RAC
> > database besides Oracle software before upgrading from 8.1.7 to 9.2?
 Or do
> > you imply that I should move datafiles of 8.1.7 database to raw devices,
> > rename them in control file and init.ora and 8.1.7 will work with
 these raw
> > devices? And then I should do the upgrade to 9.2 RAC?
> >
>
>
> Well roughly then only difference between a single instance database
> and a multiple instance database is that a single instance database
> has a single thread of redo logs (subdivided in groups/member groups)
> while a multiple instance database needs a private thread of redologs
> for each instance. To create a private redo log thread you have to use
> the word thread while creating the redo logs.
> Anyway if you omit the THREAD parameter in init.ora of your instance
> would acquire the first public redo log thread avaiable, but i havent
> never tested.
> So for the upgrade i think you would
> 1) upgrade your database to oracle 8.1.7, close it and take a cold
> backup of everything
> 2) copy all the files to raw device (or volumes) with dd
> 3) make links named likes your databafiles that points to your raw devices
> (e.g. if you have a datafile that resided in
> /oracle_data/ORCL/system_orcl_1.f and you have placed in
> /dev/vx/.../vol101, you should
> ln -sf /dev/vx/...vol101 /oracle_data/ORCL/system_orcl_1.f )
> the database for what i know has to believe it's referencing a file on
> your filesystem.
> 4) modify your init.ora if you want to change something thenopen the
> database with oracle 9.2 and upgrade it with the upgrade scripts that
> resides in your oracle_home_9.2/rdbms/admin
> 5) shutdown the database
> 6) mount it, then create the private redolog threads, one for each
> instance you are to use with RAC
> 7) possibly dropping the public redo log of the old database
> 8) shutdown the database, modify your init.ora (or spfile) with
> the instance and thread parameters (INSTANCE=1, THREAD=1 for the first
> node, INSTANCE=2, THREAD=2 for the second node and so on)
> and your migration would be complete
>
>
> > Should I create additional redo logs for 8.1.7 and rename all redo
 logs
> > to the
> > format which is recommended by Oracle for RAC? But 8.1.7 does not know
> > about threads...
>
>
> You can add threads of redo logs after you have completed the migration
> to 9.2...and the paramer THREAD exists since oracle8 (maybe oracle 7)
> but maybe you need to have the parallel option enabled to use it.
>
> if you need further infos feel free to contact me by email;
> sprry for my bad english but i think i am an anti-genius of foreign
> languages :)
>
> ciao
Received on Thu Sep 12 2002 - 20:08:32 CDT