Yes, I think so. A single HBase cluster can't (or, at least, really shouldn't) 
span multiple data centers; the strong consistency you refer to is only 
available within a cluster. 

But the replication you were referring to in your initial email is cross-data 
center, between two or more clusters. That's where you can't get strong 
consistency. 

Ian



On Dec 7, 2012, at 1:38 PM, "sriraam h" <[email protected]> wrote:

> "Strongly consistent reads/writes: HBase is not an "eventually consistent" 
> DataStore. This makes it very suitable for tasks such as high-speed counter 
> aggregation"
> 
> http://hbase.apache.org/book/architecture.html
> 
> 
> Am I missing something ?
> 
> - Sri
> 
> 
> 
>> ________________________________
>> From: Ian Varley <[email protected]>
>> To: "[email protected]" <[email protected]> 
>> Sent: Friday, 7 December 2012, 23:49
>> Subject: Re: PROD/DR - Replication
>> 
>> Juan,
>> 
>> No; that would mean every single write to HBase has to wait for an ACK from 
>> a remote data center, which would decrease your cluster throughput 
>> dramatically. If you need that, consider other database solutions.
>> 
>> Ian
>> 
>> On Dec 7, 2012, at 12:14 PM, Juan P. wrote:
>> 
>> I was reading up on HBase Replication and wanted to make sure I'm not
>> missing something.
>> 
>> Given that replication happens asynchronously the replication strategy has
>> an "eventually consistent" policy.
>> 
>> I was considering using this feature for Production / Disaster Recovery
>> setup.
>> 
>> Is there a way to enforce Consistency so that if my PROD environment should
>> ever go down, I can 100% sure that DR will be completely up to date?
>> 
>> Thank you,
>> Juan
>> 
>> 
>> 

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