Data Guard vs Streams for a RAC database

We are in need of preparing a backup server for one of the business critical RAC databases at our company. Since the DRC setup will take some considerable time, application owner requested to maintain a backup database server (active) for the database to be able to survive from any scary incidents. Although my vote goes to Data guard configuration, we would like to choose the best and a very light weight option to fulfill the requirement. Any pros and cons or comparision between these two would be highly appreciated.

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Best Regards,

Syed Jaffar Hussain
Oracle Certified Master (10g)
http://www.oracle.com/technology/ocm/shussain.html
Co-author Oracle 11gR1/R2 RAC Handbook
http://www.packtpub.com/oracle-11g-r1-r2-real-application-clusters-handbook/book
Oracle ACE
http://apex.oracle.com/pls/otn/f?p=19297:4:4640302666204919::NO:4:P4_ID:186
OCP 8i,9i,10g & 11g DBA
RAC Certified Expert
Official Oracle RAC SIG Representative for Saudi Arabian region  (
http://www.oracleracsig.org/)
I blog at
http://jaffardba.blogspot.com/
LinkedIn : http://www.linkedin.com/in/sjaffarhussain
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"Winners don't do different things. They do things differently."

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