How to restore SAP instance with an existing database?

[Former Member]

Hi, I am left with only a database containing the ABAP stack only. The SAP central Instance was uninstalled without uninstalling the database. If were to proceed to restore the whole SAP system up, what do you think the method should be? Reinstall SAP as a Distributed system:

Global Host Preparation & Central Instance and leave the Database Instance out?

Some Info:

- The database and previously central Instance were on the same physical box.

- The database is up and running

Has anyone done this before? I really need advise on this.

Points will be rewarded for helpful information.

[Former Member · Accepted solution]

What is you Database: Oracle or SQL? Which Version of SAP are you using?

[Former Member · Accepted solution]

Database: Oracle 10.2

SAP version: NW2004s SR2 ABAP Central Instance

[Former Member · Accepted solution]

Annie,

First go ahead with the CI installation...This should be the first step....

When you say Oracle is up, I hope you can see the Oracle Services and you are able to open the database....

Cheers!

Bidwan

[Former Member · Accepted solution]

Hi Bidwan,

Yes, I can mount and open the database without problem. It is running. The installation guide said

1. Global Host Preparation is the mandatory step for:

- Preparing the file system ---> already exist

- Creating the profiles

- Installation the executables

I need to do this step isn't it? Though my old profiles and exeutables are still in my db, they are unreachable at this stage.

Or I can jump straight into Central Instance without Global Host Preparation and Database Instance steps?

My database has to be open and running while installation, right?

Message was edited by:

Annie Chan

[Former Member · Accepted solution]

Annie,

I guess you can directly jump to CI installtion because your profiles are still in db...so that should not be a problem...

Keep your DB up and running..and proceed with direct CI installtion...Lets see what happens...should not take much time...

[Former Member · Accepted solution]

Hi Bidwan,

Thank you for you reply. I will test it out and see how it goes.

Regards,

Annie

[Former Member · Accepted solution]

Annie,

All the best...I have not implemented this scenerioi n 2004s practically before ...but trying to relate things logically..let see what happens..

[Former Member · Accepted solution]

Yes, this is still new and I don't expect many people to have such a scenerio. Just wish to hear from experts that had rich experience in installation process, at least might be able to sort the logic out better than I do.

[Former Member · Accepted solution]

Hi Bidwan,

I did a simulation and it works, SAP is running. These are what I did:

1./ Fresh installation of NW2004s with ABAP only

2./ Remove Central Instance

3./ Leaving DB running. Installed SAP by choosing Distributed System, go thru Global Host Preparation(this step is needed to create profile directory) and Central Instance. Skip the Database Instance

Now, I am in another doubt. My existing database is a Solution Manager with ABAP only, the tables owner is SAPSSM. However, the fresh installation of NW2004s is SAPSR3. I launched the SAPInst of Solution Manager SR3, assuming the owner of this installation should be SAPSSM but there isn't a choice to install ABAP only.

Will this cause inconsistency?

[Former Member · Accepted solution]

Annie,

I am not able to completely understand your problem, but what appears to me is that the owner of the old database was SAPSSM and after you did the installation the new owner is SAPSR3.

1. So do you say that both the owners exist? select username from dba_users;

2. Login to SAP and go to a particular table say TBTCO. see the entries. Now login to DB. Do a select * from SAPSR3.<tablename>. What do you see? Are the entries that u see are same as that u saw in SAP.... Do a select * from SAPSSM.<tablename> What do you see?

[Former Member · Accepted solution]

I think I do, so let me explain :-).

1st, Annie would like to restore her SM 4.0 as it had left with Database Instance only and luckily the database is still in good shape. So inorder for her to restore her SM 4.0 without loosing her configuration, She has to install a Central Instance for ABAP stack only. However, with SM 4 installation cds you have to install SM system with dual stack (ABAP + JAVA). So this is where NW04s come into the picture.

She then perform a simple test by install a "Central System" with ABAP stack only by using NW04s cds. After that she then remove the newly created Central Instance via SAP un-install and finally try to re-store the Central Instance again by using "Distributed System" where she just skipped the installation of Database Instance b/c she want to use her existing DB instance.

However. b/c she used NW04s cd to test she found the schema name is SAPSR3 compared with her existing SM 40 database schema name SAPSSM.

Finally, I believed Annie had successfully recovered her SM 4.0 system. I hope I have explained every thing in details so that every one can understand what was the problem and how Annie go about to solve it.

Well done. Annie.

[Former Member · Accepted solution]

Yes, Loi explained the situation I am in.

For the schema ownership, fortunately, in the Check Parameter phase, we are allowed to change the owner if needed. Apparently, SAPInst is intelligent enough to pick up the schema from my database, therefore I need not do anything.

The whole process runs smoothly as long as you have the DDIC password.

I have successfully restored the SM4.0 server.