Re: does FRA is really needed ?

On Dec 17, 2007 8:16 AM, Jason Arneil <Jason_at_nominet.org.uk> wrote:
> The only reason for the FRA in a dataguard environment is if you would
> like, when you perform a failover, to have the ability to flashback the
> (now) old primary and reinstantiate it as a standby (assuming the hardware
> is useable). If you do not have flashback database set up on your primary
> when you perform a failover you will basically have to recreate a standby
> on your old primary using a backup.

That's what I thought so the real requirement is to have flashback enabled. FRA comes as a consequence.
Thanks for confirming that, Jason.

> I would think carefully, if you really want to go down the road of rolling
> your own, rather than relying on what you have already paid Oracle for.
> Why try and re-invent the wheel?

This is not re-inventing the wheel. Physical standby doesn't work for data warehouses loaded with NOLOGGING.
There are two common ways I'm aware of to have DR for DW: - have two parallel DW running with data load job running for both - incrementally updated standby

I agree it's not straightforward Data Guard configuration and requires much more efforts and careful consideration how it's maintained and how switchover and failover scenarios are handled.

100 GB/hour is actually a lot and I'm not sure if OP meant that this is current redo generation rate with bulk of loads done with NOLOGGING or it's estimated rate with FORCE LOGGING.

Cheers,
Alex

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