SAP An example of a DB Backup Strategy

An example of a DB Backup Strategy

Our SAP DB Backup strategy:

• Full Online Backup on 00:00 from Tuesday to Saturday.
• Redolog on 06:00 from Monday to Saturday
• And Once a month full offline backup

Is this good enough or need improvement?

An example of a DB Strategy is as follows:-

• Full online SAP backup every day at 20:00 (including weekends)
• Full OS filesystem (minus SAP data) every weekday.
• Continuous archive logging from 15:00 to 11:00 next day (weekdays) and 15:00 to 14:30 (weekends).
• Archive log deletion at 14:45 every day.
• We perform a parallel backup on 2 tapes using 3 x 5 DLT tape autoloaders using a 7 day rotating tape cycle. OS backup onto single DAT.
• The tapes are stored offsite and brought in every weekday. On Friday the Friday,
• Saturday and Sunday tapes are brought in.

The only problem I can see with the strategy is if the system crashes at 05:55 on Monday and needs a restore, you could lose a lot of data as you are missing backups on Sunday and Monday, and archive logs from Sunday.

With this strategy if this happens you will be restoring the data from 00:00 Saturday and the logs from 06:00 Saturday. This means you could lose 48 hours worth of data.

Is your operation 24 x 7 or 24 x 5? If 24 x 5 it shouldn't be too bad unless you run weekly jobs over the weekend.

Do you have single tape drives or multiple autoloaders?

Is there anyone there to change the tapes over the weekend?

My own personal suggestion would be to forget the offline backup as you do not really want to restore data which could be a month old so why bother shutting the system down every month to back it up. I would perform a daily online backup every
possible day and continually archive the redo logs with a window for changing the tapes. If nobody is there over the weekend to change the tapes, run your archiving continually through the weekend i.e. start on Friday and finish on Monday.

SAP Evaluating Online Re-Organization Tools

Evaluating Online Re-Organization Tools

Content Author: Christophe Rabeau

We are evaluating online reorg tools for an Oracle SAP database which is soon to be of 1 Terra Bite size. I would like some guidance for online reorg.tools and experiences of using some of them.

I use SAP 4.6C under Oracle 9.2 under AIX 5.1 on Risc6000 medium-performance machines.

I experienced some reorganizations SAP online, due to the PRD system that must always be up.

Fisrt, consider that the entire reorg is not possible when SAP is online, because of permanent tables (system tables and so on) that could not be exported/imported while running.

An entire TABLESPACE reorganization is no more suitable because of the long runtime between 2 offline backups.

So you can reorg only some tables/indexes or single objects. Be sure that the objects should not be accessed during the reorg, so it will fail. For a particular case, for example a BIG table, I experienced serious perf problems :

JVTLFZUO table : 10 Gb data + 17 GB indexes = 37 GB to be reorganized.

When SAP is online, it took about 13 hours (4 procs, 8 GB RAM)
When SAP is not available for users, it took less than 5 hours !!!

So my advice is :
- don't reorg too big tables with SAP online.
- don't reorg system tables with SAP online.
- you'd better to perform a reorg by night or in a lower user activity.
- you'd rather to reorg with SAP down for perfs point of views.
- always perform an OFFLINE backup before reorg, because the reorg is not always successful.

SAP Perform the Backup for each Client Separately

Perform the Backup for each Client Separately

I have 2 clients in one server. The database is SQL.
Would like to perform the backup for each client separately so that I can restore per client.
So far, I've only found information saying that we have to do the entire backup for the database and that individual client backup is not good.

Can anyone advise me on how to perform individual client backup and how's the data integrity.

Sharon

It little confusing with your statement when you are saying that "I have two clients in server".
Or is it rather you want to say that you are having two database instaces on one server.

Scenario 1:
You have One server hosting more that one client as you say. Lets assume it to be Developement & Test client on single databse. Here please note that any SAP DB instace always have more than two clients. The Defaulta clients are:
* Client 000 : SAP AG Konzen
* Client 066 : SAP Early Watch Client.

In addition you have your client specified as
* Client XXX : This will be your production / dev / test client

You can have as many client as you want in a system. Well that really depends on amount of workload and the hardware capacity of the server.

Scenario 2:
You have more that one Database instance on single server. Here you have a choice of having same programs files with multiple databases and or having two different databse instaces with saperate program files. Like in case of oracle you can have two oracle instances Oralce 8i and other with Oracle 9i or any combination you like.

Now your question "Can I take backup of the single client ?"
Ans : Well its possible but then this is not a normal scenario. Its not call as a backup though. You can use the fuctionalities such as client export or client copy procided by SAP.

Second Question : " What about the data integrety ?"
Ans : The option of Client Copy or Client Export are used for specific purpose. You are required to do changes / configure required by the specific fuctionality.

Important Points:
In case of database failuer you would need the complete backup of the database and not just particultal client.
SAP Database does not contain only data but also contains the programs as well. And some of these infomation (Data as you would call) is shared across multiple client in one databse instance.
Hense it is important to restore the complete databse to retain the integrity of the system.
In case of having different DB instances on server you can perform backup of the individual databases. That is sufficient to bring the individual system up after the database failuer.

Hope this is sufficient for your doubt.