Backup methodologies

[chikkodi]

Hi,

We can do backup of a database using the Enterprise Manager. Is this sufficient ?
We can also backup a database using sql scripts and manually copying over the datafiles etc.

What is the difference between the above two approaches ?
Is either one adequate, or do we need both approaches ?

Thanks a lot for your help

Neelima

[Halo]

The difference is that, in one case, you are using a tool to take the backup, while on the other hand, you manually prepare the backup script are use that. In either case, either one is fine. Usually, ppl prefer to prepare the scripts and run them.

[sreddy]

One would do. People preferences. In big shops where one wants to see/monitor all of their database administration activiities in a single place. So they use Enterprise Manager.

Its lot easy if you use Enterprize manager as you can see all of the databasee backups status etc in one place to make sure everything was backedup perfectly than login to each box and see the crontab logs/status.

I Prefer to use Enterprise Manger than crontab scripts.

It depends on howmany of the databses you manage on howmany boxes ? If the answer is many your option is Enterprise Manger otherwise whatever that makes you comfortable.

Here I am emphasizing on running backup jobs from Enterprise Manger which invokes your custom scripts.

[Edited by sreddy on 01-18-2001 at 12:43 PM]

[chikkodi]

Thanks a lot for your replies.

How about the Backup Manager that comes with Enterprise Manager ?

[sreddy]

I guess Backup Manager is nothing but RMAN or equivalent product component of Enerprise Manager.

It can be used. But, you have to test it thouroughly before, as personally I didn't use it, but we will be using it soon in couple of months.

At this moment, I don't know the issues with it.

[sambavan]

You can use OEM, to perform the backup operation. What happens basically is that when you create the backup, depending on the choice to use RMAN/OS the OEM would create the job for this operation. Then it schedules according to your preferences. As, some folks suggested above, it is in a way a good tool to create jobs and events and then monitor them. But the problematic matter is that you have to make sure that your management server is up and running and the corresponding intelligent agents on the nodes are also up and running. When you create the job, I think that OEM does not create it in the database, as a result, if your OEM were to fall down for some reason, your jobs will also fail from getting executed. One other things is that when you do some patch installation, your OEM also needs to get upgraded at times, one of the painfull things is that you might even have to drop your repository and recreate one. This happen to me.

If you are running a job through the crontab or dbms_job options, then you don't have to worry about the possible failures during upgrade. One of my suggestions would be to use Oracle's Recovery Manager(RMAN) to create a catalog and some backup scripts and then you could invoke it through some shell script from a crontab. The possibility of this failing is very less.

Good luck,
Sam

[chikkodi]

Thanks a lot for all your answers