Re: rman block recovery
From: joel garry <joel-garry_at_home.com>
Date: Thu, 12 Apr 2012 13:30:20 -0700 (PDT)
Message-ID: <cf21d93e-57f1-4339-9f3f-d5fa997b4915_at_x17g2000yqj.googlegroups.com>
On Apr 12, 11:22 am, Mladen Gogala <gogala.mla..._at_gmail.com> wrote:
> On Thu, 12 Apr 2012 09:13:19 -0700, joel garry wrote:
> > Look again at the link I posted, restrictions, you can't do PITR with
> > block recovery. But the example shows you can limit the time of the
> > backup restored _from_. An interesting distinction, eh? It would be
> > inconsistent, but I'm presuming the inability to write to it once
> > corrupt would prevent the inconsistency, because the final redo stream
> > vector would be the last good one. There should be some testing done
> > around this, presumptions aren't so good, and something is bothering me
> > about the redo getting ahead of the data file, especially if the
> > corruption is not detected until backup time.
>
> I have never used block recovery with RMAN. Modern SAN equipment is very
> reliable, I've never had any need to do so. Have you done it? What were
> the circumstances?
>
> --http://mgogala.byethost5.com
Date: Thu, 12 Apr 2012 13:30:20 -0700 (PDT)
Message-ID: <cf21d93e-57f1-4339-9f3f-d5fa997b4915_at_x17g2000yqj.googlegroups.com>
On Apr 12, 11:22 am, Mladen Gogala <gogala.mla..._at_gmail.com> wrote:
> On Thu, 12 Apr 2012 09:13:19 -0700, joel garry wrote:
> > Look again at the link I posted, restrictions, you can't do PITR with
> > block recovery. But the example shows you can limit the time of the
> > backup restored _from_. An interesting distinction, eh? It would be
> > inconsistent, but I'm presuming the inability to write to it once
> > corrupt would prevent the inconsistency, because the final redo stream
> > vector would be the last good one. There should be some testing done
> > around this, presumptions aren't so good, and something is bothering me
> > about the redo getting ahead of the data file, especially if the
> > corruption is not detected until backup time.
>
> I have never used block recovery with RMAN. Modern SAN equipment is very
> reliable, I've never had any need to do so. Have you done it? What were
> the circumstances?
>
> --http://mgogala.byethost5.com
Haven't done it. The only corruption I've seen is a damager impatiently removing too many drives on a RAID-5, during testing. That did not corrupt a few blocks...
jg
-- _at_home.com is bogus. http://webdemo.visionobjects.com/equation.html?locale=defaultReceived on Thu Apr 12 2012 - 15:30:20 CDT