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From Morgan Segalis <msega...@gmail.com>
Subject Re: Having 2 nodes with 100% Ownership ?
Date Mon, 12 Aug 2013 23:41:56 GMT
Hi Robert,

Thanks for helping me (again). As you know, I'm a real newbie.

So I fetched the whole apache-cassandra (not the /var/lib/cassandra) folder from my first
server to my second server.
So I'm sure to use the exact same version.
I have changed the token of the second node to 85070591730234615865843651857942052864 as http://blog.milford.io/cassandra-token-calculator/
gave me.

Here's my current topology : 

create keyspace mykeyspace
  with placement_strategy = 'NetworkTopologyStrategy'
  and strategy_options = {DC1 : 1}
  and durable_writes = true;

so I should update with 

update keyspace KEYSPACE_NAME with storage_options = {DC1 : 2};

and then :

$ nodetool repair (on both nodes)

Knowing that Server 1 and Server 2 are from the same Provider, but not on the Same Data Center
(Ping is really fast, not sure if that comes in count : ± 0.350 ms)

Should I change the cassandra-topology.properties file ? (it is currently the out-of-the-box
version)

Thank you.

Morgan.


Le 13 août 2013 à 01:22, Robert Coli <rcoli@eventbrite.com> a écrit :

> On Mon, Aug 12, 2013 at 4:19 PM, Morgan Segalis <msegalis@gmail.com> wrote:
> It is still a little fuzzy when it comes to calculate a token for 50% distribution…
How do I do that, it is not like I wanted to have 10,23% on one node, and 89,77% and the other
;-)
> 
> The "feature" which picks a random token and results in distributions like this has been
removed from upstream.
>  
> for 2 nodes it tells me to put 85070591730234615865843651857942052864 on the second node.
(For 2 node calculation) and the first one at 0.
> 
> How come I can get 50% on both nodes if all data are replicated ?
> 
> Briefly, you will get effective ownership = 100% if you up the RF so that it = N.
> 
> Two nodes, each of which own 50% of the "token range", but with a RF=2 means "ownership"
is 50%, but "effective ownership" is 100%.
> 
> =Rob
>  


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