Re: Backup strategy

ernestyik_at_cuhk.hk (Ernest Yik) wrote:

>On 2 Jun 1995 19:57:18 GMT, mreagan (mreagan_at_fast.net) wrote:
>:> Am I right to think like this? Make a full backup one day, and then
>:> we'll only have to backup the data with export. [......]
 

>: The correct way (IMHO) is to set your database up to run in archive log
>: mode. Shut down the database and perform a cold backup. Then archive
>: the offline redo logs each night (and possibly perform nightly hot
>: backups, depending on your update levels).
 

> I believe that we will perform hot backup weekly and cold
>backup on a monthly basis.

Cold backups are the easiest to deal with.

>: If you experience a drive
>: failure, you would need to recover the data files from the most recent
>: cold or hot backup, and then apply the archive logs from that point on.
>: You will be able to recover your database up to the time of the crash,
>: losing only the uncommitted transactions at that time.
 

> I believe recovering up to the time of crash is not possible if
>the archived redo logs are also damaged together with the drive failure?

Oracle can be told to mirrow redo log files.

>: Yes, its a pain to run in archive log mode, but if you need your data
>: (and who doesn't), it is really the best option.
 

> What is the pain actually? (Our database is still not in
>archivelog mode now) Performance degradation? Hard Disk space
>consumption?

If you do cold backups you olny need to keep the log files since the last backup.

> Thanks for your valuable information.
 

>Regards,
>Ernest Yik.
 

>--
> * Origin: VAXlab : Home of Ernest * Hong Kong * Internet: ernestyik_at_cuhk.hk
Received on Tue Jun 06 1995 - 00:00:00 CEST