http://www.datastax.com/docs/1.0/cluster_architecture/replication
2013/5/20 Bryan Talbot <btal...@aeriagames.com>
> Option #3 since it depends on the placement strategy and not the
> partitioner.
>
> -Bryan
>
>
>
> On Mon, May 20, 2013 at 6:24 AM, Pinak Pani <
> nishant.has.a.quest...@gmail.com> wrote:
>
>> I just wanted to verify the fact that if I happen to setup a multi
>> data-center Cassandra setup, will each data center have the complete
>> data-set with it?
>>
>> Say, I have two data-center each with two nodes, and a partitioner that
>> ranges from 0 to 100. Initial token assigned this way
>>
>> DC1:N1 = 00
>> DC2:N1 = 25
>> DC1:N2 = 50
>> DC2:N2 = 75
>>
>> where DCX is data center X, NX is node X. *Which one the following
>> options is true?*
>>
>> *Option #1: *DC1 and DC2, each will hold complete dataset with keys
>> bucketed as follows
>> DC1:N1 = (50, 00] => 50 keys
>> DC1:N2 = (00, 50] => 50 keys
>> ----
>> Complete data set mirrored at DC1
>>
>> DC2:N1 = (75, 25] => 50 keys
>> DC2:N2 = (25, 75] => 50 keys
>> ----
>> Complete data set mirrored at DC2
>>
>> *Option #2: *DC1 and DC2, each will hold 50% of the data with keys
>> bucketed as follows (much the same way in a single C setup)
>> DC1:N1 = (75, 00] => 25 keys
>> DC2:N1 = (00, 25] => 25 keys
>> DC1:N2 = (25, 50] => 25 keys
>> DC2:N2 = (50, 75] => 25 keys
>> ----
>> data is divided into the two data centers.
>>
>> Thanks,
>> PP
>>
>
>
--
Sincerely yours,
Apostolis Xekoukoulotakis
