Re: Online backup: Backup online redologs?

PMFJI
"Charles Fisher" <Charles.Fisher_at_alcoa.com> wrote in message news:Pine.GSO.4.31.0105081439340.805-100000_at_unknown...
> Number two:
>
> What if the server catches fire? What if some idiot spills a coke into the
> disk array? What if we have a tornado and I see my server sailing past my
> office window?
>
> It might be a tad difficult to extract the online redo logs in that case.

True, but

1. You'd be using a disaster recovery scenario at this point right. That has absolutely zilch to do with backup (hot or not).
2. So what if you operations base is destroyed by earthquake and all you've got is your backup tape. Does you business really, really, really care that it has lost 10 minutes worth of activity in the current redo log. I'm damn sure it won't. It'll be more bothered by the loss of the operations director and DBA!

>
> I ABSOLUTELY MUST have everything that I need to restore the database on a
> tape that I can hold in my hand, and it must be from a hot backup. If I
> can't have that, then I don't want Oracle (and I don't know why anybody
> else would).
>
> I don't know why there isn't a furious uproar of people asking the same
> set of questions about this that I am. I just don't understand it.

Well what system do you prefer that can backup data *as it is written* to the database to a tape you can hold in the palm of you hand. It doesn't exist. In fact I'd go so far as to say it can't exist. You can do things to help avoid the nightmare (like multiplexing redo logs) but in the end it is *always* possible to destory both your data and you backup method. If you absolutely MUST have this functionality go write an RDBMS that provides it. Oracle can't and won't. If you are writing data changes to disk then whatever file is being written to is not suitable for hot copying. It can't be.

>
>
> Number three:
>
> I need to clone from time to time from our production to development
> systems. My backup method works great double-duty.

But recognise that cloning is not backup. It is best to use the most appropriate backup solution for you needs *and* the most appropriate cloning solution. The two may or may not be the same.

--
Niall Litchfield
Oracle DBA
Audit Commission UK