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From AJ>
Subject Re: Docs: Token Selection
Date Fri, 17 Jun 2011 16:07:24 GMT
Thanks Jonathan.  I assumed since each data center owned the full key 
space that the first replica would be stored in the dc of the 
coordinating node, the 2nd in another dc, and the 3rd+ back in the 1st 
dc.  But, are you saying that the first endpoint is selected regardless 
of the location of the coordinating node?  Are you saying that the 
starting endpoint is the one closest to the row token regardless of the 
dc?  So, it is possible that a replica might not even get stored in the 
dc of the coordinator at all depending on how many dc's there are, rf, 
starting token assignments, etc.?

On 6/17/2011 12:20 AM, Jonathan Ellis wrote:
> Replication location is determined by the row key, not the location of
> the client that inserted it.  (Otherwise, without knowing what DC a
> row was inserted in, you couldn't look it up to read it!)
> On Fri, Jun 17, 2011 at 12:20 AM, AJ<>  wrote:
>> On 6/16/2011 9:45 PM, aaron morton wrote:
>>>> But, I'm thinking about using OldNetworkTopStrat.
>>> NetworkTopologyStrategy is where it's at.
>> Oh yeah?  It didn't look like it would serve my requirements.  I want 2 full
>> production geo-diverse data centers with each serving as a failover for the
>> other.  Random Partitioner.  Each dc holds 2 replicas from the local clients
>> and 1 replica goes to the other dc.  It doesn't look like I can do a
>> ying-yang setup like that with NTS.  Am I wrong?
>>> A
>>> -----------------
>>> Aaron Morton
>>> Freelance Cassandra Developer
>>> @aaronmorton

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