Hi Aaron,

I have open a ticket in Jira : https://issues.apache.org/jira/browse/CASSANDRA-5310
Reading the user using the QUORUM consistency level means that in case of network outage, you are unable to open a connection, and all your data become unavailable.

Regards.

Jean Armel

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

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