Re: Can Cassandra work efficiently with multiple data directories on multiple disks?

2014-04-30 Thread Yatong Zhang
Thank you Arindam, that helps On Wed, Apr 30, 2014 at 5:32 PM, Arindam Barua wrote: > > > This thread should answer your questions: > > > http://stackoverflow.com/questions/15925549/how-cassandra-split-keyspace-data-when-multiple-dirctories-found > > > > > > *From:* Yatong Zhang [mailto:bluefl.

Re: Old tables still exist

2014-04-30 Thread Robert Coli
On Wed, Apr 30, 2014 at 5:36 PM, Michael Shuler wrote: > For the benefit of the ML, CASSANDRA-7127 was opened, and snapshots will > not be taken, if conf/cassandra.yaml has: > > auto_snapshot: false > Didn't this already exist as a (not-in-the-default-conf-file) option? I was aware of it (somethi

Re: Old tables still exist

2014-04-30 Thread Michael Shuler
On 04/30/2014 05:29 PM, Robert Coli wrote: On Wed, Apr 30, 2014 at 3:25 PM, Batranut Bogdan mailto:batra...@yahoo.com>> wrote: During the development of our entire system we generated huge tables (GB or TB) then had to drop them since we changed the definition. This takes up space. T

Re: Old tables still exist

2014-04-30 Thread Robert Coli
On Wed, Apr 30, 2014 at 3:25 PM, Batranut Bogdan wrote: > During the development of our entire system we generated huge tables (GB > or TB) then had to drop them since we changed the definition. This takes up > space. There is a constant write on the system so we want to optimize our > cluster. B

Re: Old tables still exist

2014-04-30 Thread Batranut Bogdan
Well this is not good at all... During the development of our entire system we generated huge tables (GB or TB) then had to drop them since we changed the definition. This takes up space. There is a constant write on the system so we want to optimize our cluster. Basicaly not expanding untill t

Re: Old tables still exist

2014-04-30 Thread Robert Coli
On Wed, Apr 30, 2014 at 3:00 PM, Batranut Bogdan wrote: > Is there a way to get cassandra to remove these old and unused tables? > Those directories have to exist after DROP because snapshots taken when you drop, and the snapshots are in a subdirectory of those directories. nodetool clearsnapsh

Old tables still exist

2014-04-30 Thread Batranut Bogdan
Hello all, I have a question. I looked in the keyspace directory and saw that old dirs still exist after dropping the corresponding table. eg drop table t1 and in /data/keyspace I still see the t1 dir.  Is there a way to get cassandra to remove these old and unused tables?

Error "evicting cold readers" when launching an EmbeddedCassandraService for a second time

2014-04-30 Thread Clint Kelly
Hi all, I have a unit test framework for a Cassandra project that I'm working on. For every one of my test classes, I delete all of the data file, commit log, and saved cache locations, start an EmbeddedCassandraService, and populate a keyspace and tables from scratch. Currently, the unit tests t

RE: Can the seeds list be changed at runtime?

2014-04-30 Thread Arindam Barua
>> For new nodes that you want to bootstrap into the cluster you can specify >> any nodes you wish. Note that you want to keep your seed list consistent across your cluster though. From: Mark Reddy [mailto:mark.re...@boxever.com] Sent: Tuesday, April 29, 2014 2:26 AM To: user@cassandra.apache.o

RE: Can Cassandra work efficiently with multiple data directories on multiple disks?

2014-04-30 Thread Arindam Barua
This thread should answer your questions: http://stackoverflow.com/questions/15925549/how-cassandra-split-keyspace-data-when-multiple-dirctories-found From: Yatong Zhang [mailto:bluefl...@gmail.com] Sent: Wednesday, April 30, 2014 2:03 AM To: user@cassandra.apache.org Subject: Can Cassandra work

Can Cassandra work efficiently with multiple data directories on multiple disks?

2014-04-30 Thread Yatong Zhang
Hi there, I have the following configuration: data_file_directories: > - /data1/cass > - /data2/cass > - /data3/cass > - /data4/cass > - /data5/cass > - /data6/cass > and each directory resides on a separate stand-alone harddisk. My questions are: 1. Will Cassandra split

Re: Cassandra Client authentication and system table replication question

2014-04-30 Thread Julien Campan
Hi Anand, Yes you should change the replication factor of the system_auth keyspace. By default it is RF = 1 and it s very dangerous in production. If you loose one node an user can loose all access.(it is a SPOF) You should use a multi DC replication for this keyspace. Regards, Julien 2014-04

RE: Some questions to adding a new datacenter into cassandra cluster.

2014-04-30 Thread Arindam Barua
Answers inline. From: Lu, Boying [mailto:boying...@emc.com] Sent: Wednesday, April 30, 2014 12:20 AM To: user@cassandra.apache.org Subject: Some questions to adding a new datacenter into cassandra cluster. Hi, All, I need to add a Cassandra (running on a three nodes) fresh installed in a datac

Some questions to adding a new datacenter into cassandra cluster.

2014-04-30 Thread Lu, Boying
Hi, All, I need to add a Cassandra (running on a three nodes) fresh installed in a datacenter say DC3 to existing Cassandra datacenters say DC1 and DC2. I read the document about it at http://www.datastax.com/documentation/cassandra/2.0/cassandra/operations/ops_add_dc_to_cluster_t.html But I h