Re: Use LGWR or ARCH for standby db

"Carsten Grammes" <cgrammes_at_gmx.net> wrote in message news:3e5e295e.109126906_at_gandalf.dialogika.de...
> Hello world,
>
> I'm trying to figure out which would be the best method to use. I'm
> working on 9.2 (W2K) and have 2 identical machines connected over
> network. The network connection has proven not to be reliable in the
> sense that (out of my control) s.o. plugs out the network or shuts
> down the standby machine etc.
>
> I started with classical standby db using the archiver to send the
> archived logs to the standby machine (8i style feature).
>
> My reqeuirement is to have the primary server up and running 7x24.
> Network breakdown to the standby must not inhibit the primary db. That
> means: "SYNC" must not be used.
>
> Do I have any advantage of using LGWR ASYNC over ARCH? AFAIK I can
> specify the max number of blocks after which LGWR sends an update to
> the standby. I could however as well have a script forcing log
> switches regularly on the primary machine. How does the LGWR mechanism
> behave in case of longer network breaks, say so long that all log
> groups are reused in the meantime? Does it then send archived logs
> over to the standby in order to keep it up to date when network is
> back again?
>
> What are your experiences with using LGWR?

Hi Carsten,

Not good I'm afraid.

There's still a rather nasty bug that under heavy load will render your redo logs in a undetermined state, preventing them from being overwritten. Only solution is to turn off LGWR archiving and bounce the database.

Oracle aiming for a patch fix before 10i.

Cheers

Richard

>
> Thanks,
> Carsten.
>
> ---
> I want to die peacefully in sleep like my grandfather.
> Not screaming in terror like his passengers!
Received on Fri Feb 28 2003 - 06:45:10 CST