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From Alain RODRIGUEZ <arodr...@gmail.com>
Subject Re: Multiple Cluster vs Multiple DC
Date Tue, 12 May 2015 15:53:03 GMT
Hi Anuj, thanks for the answer.

"Multiple DC is usually useful in case u need Geo Redundancy or have
distributed workload" --> I agree.

"Do u have these clusters at same physical location?" --> I am asking a
question about theory actually...

The exact question is: What is the difference of having 2 distinct clusters
VS having one cluster (same seeds, cluster name) but with 2 Keyspaces split
into 2 Cassandra DC and not replicated in both cluster ?

C*heers,

Alain

2015-05-05 14:43 GMT+02:00 Anuj Wadehra <anujw_2003@yahoo.co.in>:

> Multiple DC is usually useful in case u need Geo Redundancy or have
> distributed workload. Do u have these clusters at same physical location?
> If 3 nodes are at diff locations dont u need geo red for disaster ? Whats
> ur RF for cf?
>
> Thanks
> Anuj
>
> Sent from Yahoo Mail on Android
> <https://overview.mail.yahoo.com/mobile/?.src=Android>
> ------------------------------
>   *From*:"Alain RODRIGUEZ" <arodrime@gmail.com>
> *Date*:Tue, 5 May, 2015 at 2:50 pm
> *Subject*:Multiple Cluster vs Multiple DC
>
> Hi,
>
> tl;dr : How to choose between having a Cluster with 2 DC and having 2
> separate clusters as follow:
>
> "cluster_name: mycluster
> KS1 {DC1: 3, DC2: 0} and KS2 {DC1: 0, DC2: 3}"
>
> OR
>
> "cluster_name: cluster1
> KS1 {DC: 3}
> +
> cluster_name: cluster2
> KS2 {DC: 3}"
>
> We can use distinct columns and row to keep distinct entries, depending on
> sharding, locallity and query I know how to model this.
>
> At a higher level we have CF, Keyspace. Basically, to chose if I want to
> choose between a CF or a Keyspace, I ask myself if this table has a logical
> interest in beeing separated from existing keyspaces. This mainly depend on
> RF I want on each DC or if the table has a very specific workload that
> would need a specific attention and tuning.
>
> But when to decide having multiple cluster instead of multiple DC with
> each DC its Keyspace ?
>
> Thanks for any enlightening you can give me around this.
>
> C*heers,
>
> Alain
>
>
>

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