Oracle: In case of hot backup n cold back all the files of the databases are copied but they are copied where?

Question

R they copied from memory to DISK?

Plz tell me where they are copied? WHERE?????

Answer 1

Sounds like you need to restore?
Good backups are done of the entire database, either all offline at once (cold backup) or online (hot backup). Hot backups can run all at once, by tablespace, datafile, different incremental levels.

Backups may be done to tape or disk (direct attached or network). Sometimes backups are done to disk (for speed) then to tape later.

In general, backup commands are usually placed in some sort of script, which is run on some sort of schedule. Ad hoc or "one-off" backup commands are sometimes stored in scripts also.

Find these scripts and they will tell you where your backups are going initially; either they will specify a location or none will be specified and your first guess is that things are going to a default location.

Try to determine if your database is being backed up with RMAN (catalog, OS scripts, media management layer such as netbackup).

Are shell scripts being used (UNIX), log on as the oracle software owner (e.g. oracle) and type 'crontab -l'. If you are not familiar with reading the cron scheduler table, type 'man crontab'.
They may also be scheduled via atjobs. It's either 'man at' or 'man atjob' to read that scheduler.
Sometimes the jobs are run as root, so ask the system administrator to check the atjobs and cron jobs scheduled under root.
For windows, look into the job scheduler to see which batch jobs are running. Use right-click and Edit to open batch jobs, do not double-click on them.

If nothing turns up there, then turn your attention to rman. On your UNIX server, logon as the Oracle software owner, ensure your environment is set correctly (. oraenv) and then try :
rman target /

This should get you into your current database. Make note of the database ID (DBID) that is displayed.

RMAN> list backup summary;

Hopefully many pages scroll by, indicating many backups were done. Verify that the DBID for the backups match this database ID, if not, make a note of the database ID that is displayed.
If many pages scroll by, for this database's DBID, then you are most likely using your controlfile as the catalog and not a catalog ddatabase. Have a look to see where the backups are being done. Disk backup will look like :
7059 B F A DISK 16-JUN-06 1 1
7060 B F A DISK 16-JUN-06 1 1
7061 B F A DISK 16-JUN-06 1 1

Tape backup will look like :
7062 B A A SBT_TAPE 16-JUN-06 1 1 TAG20060616T130413

Ask your network admin to help you for tape backup.

Alternatively:
RMAN> list backup;
gives a lot more detail.

These instructions are by no means correct for you situation or exhaustive. Let me know if you need more help, this could go on for quite a bit because of the limited information.

Hope that helps.

Answer 2

Hot backups are usually accomplished via a media manager software, such as legato or netbackup.
Hot backups do not back up memory. They back up the database files. In order to take a good hot backup, you should also back up the archived redo log files that were created while the backup was running, or better yet, all the archived redo log files since the previous backup.
The media manager will write to a tape library or a backup-disk storage library.
More recent version of oracle only back up the blocks of datafiles that are occupied, and not the empty blocks.

A cold database backup can be taken by any system backup commands, just as if it were a collection of files.

***addition ***
The location where the files are copied depends on how the backup job was set up. In my location - the files are copied to backup tape.

Answer 3

During hot backup database datafiles are copied from original location to the backup destination location (database tablespaces need to be put into hot backup mode during copy operation)