dont forget shutdown transactional which waits for all current transactions
to be finished, then boots users off - they all prevent further users from
logging on by the way
"Howard J. Rogers" <howardjr2000_at_yahoo.com.au> wrote in message
news:2LMi9.36725$g9.105152_at_newsfeeds.bigpond.com...
>
> "Steve M" <steve.mcdaniels_at_vuinteractive.com> wrote in message
> news:amfvd4$6j6$1_at_spiney.sierra.com...
> > My understanding is this:
> >
> > shutdown <normal> waits for all transactions to complete and all users
to
> > log out
> >
> > shutdown immediate completes all pending transactions, preventing new
> > transactions, then waits for all users to log out
> >
>
> No. Shutdown immediate boots all users off without warning. It then spends
> time rolling their transactions back, and issues a final checkpoint. Then
it
> closes the database gracefully. What you've described is a shutdown
> transactional.
>
> > shutdown abort stops immediately, pending transactions are rolled back
> > during the next normal startup.
>
> Correct.
>
> In fact, the only functional difference between an immediate and an abort
is
> that the shutdown immediate does the rollback at shutdown time; the abort
> has to wait until the next startup. Otherwise, the two are identical in
> effect: anything that was pending at the time the shutdown command was
> issued is lost, but anything that was committed is safe.
>
> The only concern with a shutdown abort is that there is a time delay
between
> the close command and the eventual rollback (ie, when you finally get
round
> to issuing a new startup command). During that time, it is possible that
> daft things could happen to your online redo logs (which are needed for
the
> subsequent instance recovery). Were some online redo to go missing, you're
> forced to do an incomplete recovery, which means committed data would
indeed
> be lost.
>
> >
> > If I am correct, there is a likelihood of a USER thinking that a
> transaction
> > completed when indeed it was rolled back.
> >
>
> Shouldn't be, actually. The rule in Oracle is that you're transaction's
not
> committed until you see the 'Commit Processed' message -at which point,
it's
> as safe as houses, whatever sort of shutdown you do (barring the mishap
with
> the online redo in a shutdown abort scenario). Users shouldn't "think"
their
> transaction's completed until they see that message -at which point, it
> *has* been completed.
>
> > We use shutdown abort all the time.
> >
>
> And that's fine, with the one caveat I mentioned. Assuming you've
> multiplexed and mirrored you're redo, it's most unlikely that you'd ever
be
> in the "I've lost my online redo after an abort" scenario.
>
> Regards
> HJR
>
>
> > Killing sessions is (IMHO) misuse.
> >
> >
> > "Karen Abgarian" <abvk_at_ureach.com> wrote in message
> > news:3D8AB59A.441AF1D2_at_ureach.com...
> > > I wonder why nobody has responded with an opinion on WHY does oracle
> > > wait, sometimes indefinitely for shudown immediate. Likely this has
to
> do
> > > with the famous question of when exactly PMON cleans up the sessions
and
> > > releases the resources after you issue a KILL SESSION command.
> > >
> > > It seems to be very popular to shutdown abort and then startup and
> > shutdown
> > > normal.
> > > Even though this works, this is a misuse and it is natural to seek a
> more
> > > graceful solution.
> > >
> > > The contraindications of killing the sessions in a script are many but
> > have
> > > a common root:
> > > they are difficult to implement properly. A few years ago I wrote
such
> a
> > > script, it was
> > > several dozens lines of code. I am not willing to dig it up, but I
can
> > > certify that it is possible.
> > > The advantage is that you can do shutdown immediate or even normal
> > instead
> > > of
> > > shutdown abort.
> > >
> > > Regs
> > > AK
> > >
> > >
> > >
> > > Kenneth, Koenraadt wrote:
> > >
> > > > On Thu, 19 Sep 2002 12:51:46 +0200, cris <veronesic_at_libero.it>
wrote:
> > > >
> > > > >Niall Litchfield wrote:
> > > > >
> > > > >> 1. issue shutdown ABORT then immediately startup and shutdown
> normal.
> > > > >
> > > > >I was thinking about adding to my script a line that kills all the
> > > > >active oracle<sid> processes immediatly before to do the shutdown.
Is
> > > > >this a safe way to proceed or are there contraindications?
> > > > >
> > > >
> > > > Safe : NO!!
> > > > Contraindications : Dozens!
> > > >
> > > > Do as Niall says. "Shutdown abort" will kill those processes in a
safe
> > > > way.
> > > >
> > > > - Kenneth Koenraadt
> > > >
> > > > >Thank you.
> > > > >Kind regards, Cristian
> > > > >
> > >
> >
> >
>
>
Received on Fri Sep 20 2002 - 18:22:46 CDT
