Oracle extended RAC for geographical disaster recovery Oracle Tips by Burleson Consulting

 

 

Question:  What are the best options for a geographically distributed disaster recovery using RAC?  Can I use Data Guard or Streams for disaster recovery?

 

Answer: Yes, with a super-fast interconnect (e.g. "dark fiber" fiber channel connectivity) you can have geographically distributed RAC nodes, but a more common approach to extended RAC is to use Data Guard or Streams (n-way replication) for disaster recovery. 

 

For shops with high capital funding (lotsa cash), you can employ Dense Wavelength Division Multiplexing (DWDM) technology, but it becomes vary expensive over long geographical distances.

 

The choice depends mostly on costs and the volume of updates (DML) for the RAC cluster, plus your tolerance for unplanned outages during a disaster.  Fir enough money, you can guarantee continuous availability with extended RAC clusters, but if you can afford a 30 minute downtime, Data Guard or n-way Streams may be a better approach.

 

You can get expert advise on your particular shop by calling BC for check my notes below:

 

Notes on Oracle disaster recovery approaches:

 

 

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