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From Vitalii Tymchyshyn <tiv...@gmail.com>
Subject Re: Consistency level for system_auth keyspace
Date Thu, 07 Mar 2013 08:24:54 GMT
Why not WRITE.ALL READ.ONE? I don't think permissions are updated often and
READ.ONE provides maximum availability.


2013/3/4 aaron morton <aaron@thelastpickle.com>

> In this case, it means that if there is a network split between the 2
> datacenters, it is impossible to get the quorum, and all connections will
> be rejected.
>
> Yes.
>
> Is there a reason why Cassandra uses the Quorum consistency level ?
>
> I would guess to ensure there is a single, cluster wide, set of
> permissions.
>
> Using LOCAL or one could result in some requests that are rejected being
> allowed on other nodes.
>
> Cheers
>
>
> -----------------
> Aaron Morton
> Freelance Cassandra Developer
> New Zealand
>
> @aaronmorton
> http://www.thelastpickle.com
>
> On 1/03/2013, at 6:40 AM, Jean-Armel Luce <jaluce06@gmail.com> wrote:
>
> Hi,
>
>
> I am using Cassandra 1.2.2.
> There are 16 nodes in my cluster in 2 datacenters (8 nodes in each
> datacenter).
> I am using NetworkTopologyStrategy.
>
> For information, I set a RF = 6 (3 replicas in each datacenter)
>
> With 1.2.2, I am using the new authentication backend
> PasswordAuthenticator with the authorizer CassandraAuthorizer.
>
> In the documentation (
> http://www.datastax.com/docs/1.2/security/security_keyspace_replication#security-keyspace-replication),
> it is written that for all system_auth-related queries, Cassandra uses the
> QUORUM consistency level.
>
> In this case, it means that if there is a network split between the 2
> datacenters, it is impossible to get the quorum, and all connections will
> be rejected.
>
> Is there a reason why Cassandra uses the Quorum consistency level ?
> Maybe a local_quorum conssitency level (or a one consistency level) could
> do the job ?
>
> Regards
> Jean Armel
>
>
>


-- 
Best regards,
 Vitalii Tymchyshyn

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