Re: Automatic Mirroring of Rollback Segment(s) and Control File

On Tue, 03 May 2005 14:48:36 -0700, Meh-Lit Kim interested us by writing:

> Dear Gurus,
>
> Oracle's documentation mentions that it can automatically mirror online
> Transaction Logs.
>
> I'd like to know if Oracle can be configured to mirror the Rollback
> segment(s), or do we have to rely on mirrored disks to avoid having
> single point of failure for rollback segment(s) ?

Rollback (or the automatically managed versio, called Undo) segments can be considered special internal tables and changes are logged. They are effectively 'mirrored' in the 'transaction' logs.

>
> What about Oracle's control file ? Can they be automatically mirrored
> and updated when they change ? (The doc seems to imply that one has to
> manually copy Oracle's control file)

Mirrored by having the parameter (pfile/spfile) point to a list.

-- 
Hans Forbrich                           
Canada-wide Oracle training and consulting