Ha - that's what I get for trying to answer list emails from my phone. :) Ian
On Dec 7, 2012, at 1:58 PM, sriraam h wrote: Thanks Ian. I DID miss the point. The person who started the chain is a different person :) - Sri ________________________________ From: Ian Varley <[email protected]<mailto:[email protected]>> To: "[email protected]<mailto:[email protected]>" <[email protected]<mailto:[email protected]>> Sent: Saturday, 8 December 2012, 1:21 Subject: Re: PROD/DR - Replication 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]<mailto:[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]<mailto:[email protected]>> To: "[email protected]<mailto:[email protected]>" <[email protected]<mailto:[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
