need understanding on Vblock SSHPD

Vishal:

To your questions:

• I understand that extended RAC would mean that extending the storage for RAC to another data center which can go up to 100 KM and possible using VPLEX .Please confirm my understanding.

Yes, that's correct. VPLEX supports 5 ms of additional latency. This provides approximately 100 KM of distance between the two sites, but that is very configuration-specific. The important limit is the latency, not the distance. For more information on this, see this wp:

White Paper H8930: Oracle Real Application Clusters (RAC) on Extended Distance Clusters with EMC VPLEX Metro Best Practi…

• Additionally,please confirm if (assuming 4 nodes in RAC cluster) the nodes can also be separated across data centers which would mean that 2 nodes in one data center and 2 nodes in the other I think that way private interconnect speed would go down.Please confirm if that is feasible.

Yes, that is exactly how Oracle RAC with VPLEX stretched cluster works. There is a bit of additional latency in the interconnect due to the distance. Speed of light and all that.

• Let's assume that my one data center goes down would the node automatically access data from the other data center without any downtime? Is there a replication which keeps on happening in extended RAC

Exactly what VPLEX does. So, yes, your RAC cluster stays up, and all traffic will now route to the surviving nodes of the clsuter.

Regards,

Jeff