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https://issues.apache.org/jira/browse/CASSANDRA-7453?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Aleksey Yeschenko resolved CASSANDRA-7453.
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    Resolution: Not a Problem

This contradicts Cassandra design principles on a fundamental level, and cannot 
be implemented in a proper way, so closing it until something changes.

> Geo-replication in Cassandra
> ----------------------------
>
>                 Key: CASSANDRA-7453
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-7453
>             Project: Cassandra
>          Issue Type: Wish
>            Reporter: Sergio Esteves
>            Priority: Minor
>
> Currently, a Cassandra cluster spanned across different datacenters 
> replicates all data to all datacenters when an update is performed. This is a 
> problem for the scalability of Cassandra as the number of datacenters 
> increases.
> It would be desirable to have some way to make Cassandra aware of the 
> location of data requests so that it could place replicas close to users and 
> avoid replicating to remote datacenters that are far away.
> To this end, we thought of implementing a new replication strategy and some 
> possible solutions to achieve our goals are:
> 1) Using a byte from every row key to identify the location of the primary 
> datacenter where data should be stored (i.e., where it is likely to be 
> accessed).
> 2) Using an additional CF for every row to specify the origin of the data.
> 3) Replicating only to the 2 closest datacenters from the user (for 
> reliability reasons) upon a write update. For reads, a user would try to 
> fetch data from the 2 closest datacenters; if data is not available it would 
> try the other remaining datacenters. If data fails to be retrieved too many 
> times, it means that the client has moved to other part of the planet, and 
> thus data should be migrated accordingly. We could have some problems here, 
> like having the same rows, but with different CFs in different DCs (i.e., if 
> users perform updates to the same rows from different remote places).
> What would be the best way to do this?
> Thanks.



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