Re: Oracle 8i Standby Complete Recovery

"Karen Abgarian" <abvk_at_ureach.com> wrote in message news:3DB24CF1.41AAEE1A_at_ureach.com...
> >
> > > - the standby server cannot garantee 100% no data loss even with
> > > Dataguard because the primary host can go down before the Dataguard
> > > copies the changes to the standby.
> > >
> >
> > Not if you configure it so that a commit doesn't count as a commit UNTIL
> > it's been sent to the standby, and receipt of its successful
transmission
> > has been received -which is exactly how you *can* configure Data Guard
if
> > you so choose.
>
> Objection sustained :). My knowledge is a year behind. I heard this "no
data
> loss" phrase but thought it was just marketing. I'll catch up with the
manuals.
>
> There is probably no need to explain the performance impact because it is
clear
> where it's source it. Although I'll have to learn technical details, it
does
> not look
> to me upfront that the VCS should be completely thrown out of the window.
>
> >
> > >
> > > - the DataGuard (and 9iR2) software is relatively new and is probably
> > > full of bugs. If your system is critical, you may consider not to
test
> > > out
> > > the Oracle bugs on it. 8i software has plenty bugs as well but they
are
> > > KNOWN :).
> >
> > Honestly! Everyone's entitled to their own opinion, of course. But I do
> > rather wish less people would post their unsubstantiated opinion here as
if
> > it counted for anything. Have you actually tested Data Guard? It's not
> > exactly difficult to do, and then you'd be able to post some real facts
> > about it. It's not "full of bugs": and neither is the product
"relatively"
> > new, having been in the marketplace for over 12 months now.
> >
>
> No, I have not tested the DG! At our site, we are just beginning all this
> testing.
> So far we happily lived with our scripts to ship and apply the log files
to both
>
> standby databases. We don't even use managed recovery, just because you
> need to watch it. 3 minutes allowed data loss, all works perfect.
>
> I don't think I said something incorrect, though. Please notice the word
> "critical".
> It means to me that if there is some bug (maybe even one) that does
something
> to the databases I am responsible for, my head will be on the chopping
bar.
> This
> kind of bumps up my requirements for stability.
>
> To give an example, last week, during testing, we created a 9i database
listener
>
> to service two 8i and one 9i database. After bouncing one of the 8i
databases
> the listener crashed. This fact was communicated to Oracle, via a TAR,
they
> said "oops, sorry". Remember, all this is about a listener, of a software
that
> was
> in production for 12 months or more. It seems to me that the DG is a much
> bigger
> thing and the chances are ...
>
> Anyway, we'll test it and maybe there will be actual bugs to share with
the
> community. In the mean time, maybe you will post some details about how
> you tested it if you have? Please list the machine type, recovery mode
and
> configuration.
>

Hi thee to VMWare.com, and download the relevant 3.2 software. That gives you the ability to create two virtual machines which run within the confines of a single physical PC. With two virtual PCs to hand, testing Data Guard is a piece of cake. On Linux, on Windows (pick a flavour). Given it's a non-standard testing platform, I would expect the bugs to come crawling out of the woodwork. They don't.

Regards
HJR Received on Sun Oct 20 2002 - 05:31:25 CDT