Re: Oracle9i Standby Database Question

Hi Pete,

Would I be able to do a switchover if the primary server crashes because the CPU is overloaded? How long does it usually take for a primary database to failover to a standby database?

Thanks,
KC

"Pete Sharman" <peter.sharman_at_oracle.com> wrote in message news:<tjg48.9$If3.139_at_inet-nntp1.oracle.com>...
> Depends on whether this was a graceful shutdown of the primary or not. If
> it was not, then what you've done is a failover. The database that started
> as the primary cannot be used as a new standby database. This must be
> completely rebuilt using backups and logs from the new primary (old standby)
> database. The normal failover process that forces database recreation occurs
> when all of the available archive logs are applied to the standby database,
> and the standby is opened as the primary using the following SQL command:
>
> alter database activate standby database;
>
> When this command is executed, a resetlogs operation is performed
> automatically on the standby and the new logs cannot be applied to the old
> primary.
>
> If however, you've done a switchover (new in 9i) then you're OK.
> Switchover is possible only if the standby and its primary database can be
> brought to the same point in time. The prerequisites of initiating
> switchover include:
>
> .1. The primary database has been shut down in an orderly fashion; that is,
> SHUTDOWN NORMAL, SHUTDOWN TRANSACTIONAL or SHUTDOWN IMMEDIATE.
> .2. All archive logs required to bring the standby to the primary's point
> in time are available.
> .3. The primary database's online redo logs are available and intact, as
> are its data files and control files.
>
> --
> HTH. Additions and corrections welcome.
>
> Pete
> Author of "Oracle8i: Architecture and Administration Exam Cram"
>
> "Controlling developers is like herding cats."
> Kevin Loney, Oracle DBA Handbook
>
> "Oh no, it's not. It's much harder than that!"
> Bruce Pihlamae, long-term Oracle DBA
>
> "K. C." <the_ada_at_hotmail.com> wrote in message
> news:be879ba7.0201241847.545913fb_at_posting.google.com...
> > I have a question regarding Oracle9i Standby Database on Unix. Say I
> > have a primary database running on Server A and a standby database
> > running on Server B. For some reason, Server A goes down and the
> > standby database is activated. What is the quickest way to switch the
> > databases so that Server A (assuming whatever problem it had was
> > fixed) becomes the primary again?
> >
> > Thanks in advance.
> >
> > KC
Received on Sun Jan 27 2002 - 12:37:56 CST