Re: recover after lost online redo-log

Yes, each group contains two members. Each member is mirrored at the hardware level. Yes, the chance of loosing something here is very slim.

This is why I asked if there was some trick afterward to restore up to the lost log. How do you trick the engine into coming up without that log header?

Here is something more interesting:

Same scenario but in OPS envt. In a test environment, I erased the header of one of my super-mirrored ONLINE redo-logs ( by the way, using a simple command, dd to the raw device. Something that could be done by any number of people accidentally or otherwise ) on one instance. I ran transactions until that log was needed, at which time the engine puked. This is just what I expected. The other instance didn't mind a bit, and I suspect that I could drop the 'bad' redo thread and just continue on as if nothing had happened. I will test further...

-Kevin

Joel Garry <joelga_at_pebble.ml.org> wrote in article <67f20c$lcm$1_at_pebble.ml.org>...
> In article <01bd0ccb$74571380$fc7f3f8f_at_khome>,
> Kevin Brand <kbrand_at_gtetel.com> wrote:
> >
> >I understand this, however I am talking about loosing the actual device
> >file for an ONLINE redo-log, where all the header info for that log is
> >gone.
>
> That is what mirrored online redo log files are for.
>
> >
> >-Kevin
> >
> >
> >
> >John P. Higgins <jh33378nospam_at_deere.com> wrote in article
> ><349AE730.2189_at_deere.com>...
> >> That is not a trick, that's what hot backups are for. Just restore
 your
> >> backup and all the logs since and recover until cancel. Reply cancel
> >> when you have recovered the last log available.
> >>
> >> Kevin Brand wrote:
> >> >
> >> > Has anyone figured out a way to recover an instance after loosing an
 online
> >> > redo-log? A cold backup will recover to some point in time before
 the
> >> > loss. Is it possible to trick Oracle into letting me then restore a
 Hot
> >> > backup and roll the logs forward up to the log that was lost?
> >> >
> >> > -Kevin Brand
> >>
>
>
> --
> These opinions are my own and not necessarily those of Information Quest
> jgarry@eiq.com http://www.informationquest.com
> http://ourworld.compuserve.com/homepages/joel_garry
> "See your DBA?" I AM the @#%*& DBA!
>
Received on Sat Dec 20 1997 - 00:00:00 CST