Re: Active data guard vs streams/shareplex

From: <larry_m_carpenter_at_yahoo.com>
Date: Mon, 20 Apr 2009 06:04:43 -0700 (PDT)
Message-ID: <17e61b29-5c58-43e3-951d-42572ae3e224_at_z9g2000yqi.googlegroups.com>



On Apr 5, 10:13 am, dk <kigh..._at_bellsouth.net> wrote:
> We currently use sharplex to replicate from a source to a target.
> However with the 11g active dataguard we considering replacing
> shareplex.  The question is can the new dataguard serve as a replacement
> for streams/shareplex.  The source and target need to be in-sync pretty
> much real time.
>
> Thanks

If you perform read only work on the SharePlex target database then Active Data Guard would work great for you. As for being 'in-sync pretty much real time' you would not have a problem. Active Data Guard uses a Physical standby and as such has no data type nor storage restrictions and, since it use media recovery, is extremely fast. And even if you used asynchronous transport, as long as you have the network bandwidth to handle your redo generation rate your Active Data Guard standby would have no problems keeping up. This would be what is called Maximum Performance mode. If you choose to use a zero data loss configuration (remember, a physical standby is an exact copy of your Production database and as such is also a disaster recovery target) then you would move to synchronous transport using Maximum Availability. The only impact to Production here would be that the redo must be in a standby redo log (not necessarily applied yet) before the Production transactions would finish their commit. If you desired a configuration that would not allow a transaction to be committed to the Production database without being safely written at a standby site you would use Maximum Protection. This is not a mode for the faint of heart. In any case if you are not worried about data loss or are not considering the DR benefits of the standby and only want to have the data 'pretty much real time :^)' then ASYNC in Maximum Performance may be fine. There is a lot of informaiton on all of this on the Oracle Web site at http://www.oracle.com/technology/deploy/availability/index.html . I would recommend you have a look at the following.

Active Data Guard 11g - http://www.oracle.com/technology/deploy/availability/htdocs/activedataguard.html Best Practices for High Availability -- Maximum Availability Architecture (MAA) - http://www.oracle.com/technology/deploy/availability/htdocs/maa.htm

Larry Received on Mon Apr 20 2009 - 08:04:43 CDT

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