Apache Cassandra is an open source distributed database management system.

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DataStax Opscenter Agent can't connect: “Unable to locate cassandra.yaml configuration file”

I have installed Datastax Community Edition v2.0.3 on a Windows Server 2012 R2 Datacenter machine. After a vanilla install, I can't connect to the database with OpsCenter because the agent failed to ...
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1answer
484 views

Datastax OpsCenter 3.1.1 Agent JMX Authentication Error

I am using opscenter 3.1.1 and just enabled JMX username/password authentication on my Cassandra cluster. I think I've updated all my opscenter configs correctly to force the agents to use JMX auth, ...
2
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1answer
353 views

How can I view the cache-hit ratio for a single column-family in Cassandra?

I've enabled row-caching in for one of my column-families in Cassandra and I'l like to view the cache-hit ratio? I can see the cache-hit ration metric in Cassandra's OspCenter but it seems to show me ...
2
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1answer
428 views

DataStax OpsCenter 3.2.2 fails to start properly when storing collection data on different server

I'm trying to run OpsCenter 3.2.2 (enterprise edition) using a separate cluster used for storing the collection data. I specify the [storage_cassandra] tag in the cluster configuration. When starting ...
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1answer
570 views

0 connected nodes in datastax opscenter

Installed opscenterd on the separate node outside of the cluster, but within firewall ( aws security group ). Tested all possible ports between agents and opcenter server. No errors in the log.. 2013-...
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3answers
1k views

How to run datastax opscenter behind nginx

I would like to run datastax cassandra opscenter behind Nginx. But it keeps adding opscenter port (8888 by default) to all urls. Is there a config setting to disable that or something? Here is my ...
0
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1answer
672 views

Trying to install datastax opscenter - Failed to load application: cannot import name _parse

I'm not familiar with python, maybe someone could explain what's going on here? ec2-user@prod-opscenter-01:~ % java -version java version "1.7.0_45" Java(TM) SE Runtime Environment (build 1.7.0_45-...
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1answer
546 views

Changing Cassandra Tokens on 1.2.1 From 4 to 256

We initially started our cluster using one datacenter, one rack, and the Simple replication strategy. We have keyspaces with several hundred gigabytes of data. When we changed the tokens in the ...
0
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1answer
712 views

Install DataStax Ops Center EC2

DataStax Ops Center EC2 multi region setup, with 2 nodes in us-east-1 and 2 in us-west-1 Ops center is installed on a separate ec2 instance, and can see the cluster, but I cannot get the agents ...
2
votes
1answer
131 views

Cannot generate cluster reports in OpsCenter.

I cannot generate a cluster report in OpsCenter. The server and clients are running on CentOS 5.9, 64bit. Software versions: opscenter-3.2.2-1 opscenter-agent-3.2.2-1 Here is the error reported ...
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2answers
4k views

Cassandra: Exception Connecting to 127.0.0.1/9160. Reason: Connection refused?

I have installed the Cassandra 1.2.9 into my vps server which is having CentOs. I have Installed it successfully. when i run the sh cassandra-cli, i got the error message org.apache.thrift.transport....
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1answer
1k views

Apache Cassandra Split Brain

First of all, apologies if this has been asked before, I cannot find an answer on Google or StackExchange. Is it possible to put Apache Cassandra into a split-brain scenario where a network ...
3
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1answer
3k views

DataStax Enterprise server won't start: dse dead but pid file exists

When I launch it with sudo /etc/init.d/dse start it seems to work. It returns: Starting DSE daemon dse DSE daemon starting with Hadoop and Solr disabled (edit /etc/default/dse to enable) But when I ...
3
votes
1answer
1k views

“Cannot bind to port” enabling Cassandra client encryption

I'm running Cassandra 1.2 with a three-node cluster, on Debian 7. The cluster is working fine. But I want to enable encryption for clients, as documented here: ttp://www.datastax.com/documentation/...
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1answer
212 views

Rsyncable Snappy?

I have some massive Cassandra clusters that I'm maintaining on EC2. Backups offsite take a long time as the snapshots have to be tar-ed and gzip-ed and pushed over the network from the EC2 instance ...
-1
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1answer
2k views

Cassandra - Ubuntu Server Connect locally but no when connect remotely [closed]

I have a problem when I want to connect to Cassandra remotely I run it on ubuntu server and can connect to it through cassandra-cli connect localhost/9160 But when I connect remotely I have an ...
2
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1answer
99 views

I'm moving nodes around on a Cassandra cluster, and seeing “Back pressure disabled!” in the logs

I'm moving nodes around on a Cassandra cluster, and seeing Back pressure disabled! in the log. I'm also seeing (around a minute earlier) Back pressure enabled with average index queue size: 1106. ...
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1answer
31 views

Is Elastic Workload Re-provisioning still possible with DataStax Enterprise 3.1?

In the documentation of DataStax Enterprise (DSE) 2.0 there is a chapter about "Elastic Workload Re-provisioning" (http://www.datastax.com/docs/datastax_enterprise2.0/workload_reprovisioning) but it ...
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1answer
326 views

Connecting to Cassandra Cluster

I'm just getting started with Cassandra and had a few questions. I'm going to be deploying a 4 node cluster on AWS as per the DataStax documentation (http://www.datastax.com/docs/datastax_enterprise3....
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2answers
5k views

What is the best way for store images of website? [closed]

We are using cassandra database for store website information, but we are not sure how to save images. We can store them in cassandra, but we can also allocate a server for storing images. ...
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0answers
676 views

Use Amazon SNS to send nagios alerts

Is there any way by which I can send nagios alerts to Amazon SNS ? I have tried with following steps, but its giving me this error in the Nagios log file: Jul 12 11:38:23 ip-10-134-13-204 nagios3: ...
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2answers
344 views

Opening ports in EC2

I have an ec2 instance. I have opened a port in the security group for cassandra (9160) and have cassandra listening on it. If I use nmap on the instance, that port does not show up, and I cannot ...
2
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1answer
110 views

Diskless Cassandra nodes?

Would it be at all feasible to use diskless nodes for cassandra? Im imagining a setup with one 'master node' that had all the appropriate software, disks, etc and the rest would PXE boot. The setup ...
3
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2answers
691 views

Taking Cassandra Backups

We currently have 12 nodes running in our Cassandra cluster. Ultimately even if a couple of the nodes go down, we're still up and running. The paranoia in me would like to do at least one backup a day ...
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1answer
662 views

My application server can't connect to my DB Cassandra server

I have two servers. One has PHPCassa with a small app, the second has Cassandra install. Here is the error I get: An attempt was made to connect to every server twice, but all attempts failed. The ...
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1answer
141 views

Do I need to install Thrift on both my servers (Application/DB)?

Here is my situation. I have two servers. One as all my applications (PHP), the second as Cassandra DB with Solr (Solandra), and OpsCenter. I am using PHP on my application server to access my ...
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1answer
166 views

Uneven cassandra load

I have a 10 node ring & all the nodes seem to share about the same amount of data except one is considerably less does anyone have ideas? Rack Status State Load Owns ...
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2answers
400 views

Uneven Cassandra load

Should a three node Cassandra cluster with a replication factor of 3 have the same load value for all three nodes? We are using a random partitioner and NetworkTopologyStrategy. Nodetool ring shows ...
5
votes
3answers
927 views

Cassandra - hardware planning

Briefly: if I have 5 Tb of data and want to deploy this on 5 cassandra servers - does each machine need to have 5 Tb of disk space for data (not counting log space)? From the docs it sounds like at ...
0
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1answer
48 views

DB Migration switching from MySQL [closed]

I currently have a massive MySQL Data but would like to move over to Cassandra nosql. How hard of a move over would this be? I've not found any examples yet on this being done. It is possible right.
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3answers
190 views

How to choose NoSQL database engine?

We have a database with following specs: 30k records, 7mb in size 20 inserts/second 1000 updates/second 1000 range selects/second, by secondary index, approx 10 rows each needs at least one ...
2
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2answers
427 views

Dynamically changing one-node Cassandra cluster to two nodes

So I have an application that will be very dormant most of the time but will need high-bursting a few days out of the month. Since we are deploying on EC2 I would like to keep only one Cassandra ...
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vote
2answers
85 views

startup cassandra layout

We've got a relatively low-traffic site (~1K pageviews/day) hosted on a single server, and expect it to grow significantly over the next few years. I'm thinking of moving over to Rackspace ...
3
votes
1answer
2k views

Unclosed TCP connections in CLOSE_WAIT for various processes

I have cluster of several machines connected on 10GBE network (NICs are Intel 82599EB 10GBE SFI/SFP+) running under Debian 6.0 and faced with problem of hung up TCP connections in CLOSE_WAIT state. I ...
7
votes
2answers
697 views

Configuring Cassandra for consistency across multiple datacenters

Currently we run a 4-node Cassandra ring in each of two datacenters. We would like to rebuild them into a single 8-node ring. All else being equal we would really like to have consistent reads, so we ...
1
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1answer
449 views

How to find date/time used by Cassandra

Earlier this morning I noticed that one of the nodes in our Cassandra cluster is writing logs an hour in the future, despite the date/time being correct on the OS. A couple of other nodes I checked ...
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1answer
964 views

Reconfiguring data directories in an existing Cassandra node

I'm currently running a very simple single-node Cassandra box with the data files on a single disk. I'm about to add a couple of SSDs to the box and intend to add each SSD as another data directory to ...
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2answers
302 views

How to build snappy-java under FreeBSD 8.1? (build error)

I'm trying to build snappy-java for FreeBSD 8.1 to use it with cassandra (can't enable columns compression without it). Trying to build it from source and getting an error: $ hg clone https://...
2
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1answer
194 views

How do I automatically add Cassandra nodes to Windows DNS?

I'm working on building a new Cassandra cluster and I'd like to create a DNS record that will hold the IP addresses of all of the nodes. I build all of my servers in the cloud and they automatically ...
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2answers
926 views

How to find causes for the casandra killing frequently?

Installed the cassandra 0.8 in centos linux system with 1GB ram. Within an hour after starting the cassandra, it is dying frequently. Also, i can say java is also killing , which is necessary for ...
2
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1answer
873 views

Many concurrent Cassandra database connections thru SSH tunnel

I have an application that uses the PyCassa Cassandra client to open many concurrent connections to a Cassandra server. When I run the client application locally on the database server, it works. ...
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0answers
275 views

Cassandra, very long row (over 800.000 columns), row cache and manual repair

I seemed to have hit quite interesting problem recently while investigating my previous problem -- One ColumnFamily places data on only 3 out of 4 nodes We had a very long row with over 800.000 ...
1
vote
1answer
891 views

Unable to compile thrift on ubuntu

I am trying to install cassandra and thrift in my PC. I have successfully installed cassandra. But while making (using "make" command) thrift I am getting the error below: ............... ...............
0
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2answers
122 views

One ColumnFamily places data on only 3 out of 4 nodes

I have posted this on cassandra-user mailing list however didn't get any responses just yet and I was wondering whether someone here on serverfault.com will have any ideas. I seem to have came across ...
0
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2answers
306 views

Cassandra-cli could not connect to localhost

I have installed cassandra 1.0.1 stable binary in ubuntu server 11.10 amd64. But, when i try to connect using cassandra-cli with: [default@unknown] connect localhost/9160 The system always stuck,...
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2answers
1k views

cassandra node discovery

I just set up a 3 node system with ip addresses "192.168.0.101", "192.168.0.102", "192.168.0.103". I have set the seeds value on the configuration of all three machines as seeds: "192.168.0.101,192....
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1answer
597 views

Processing pre-existing log files with Flume

I have a large set of log files that I need to extract data from. Is it possible to use Flume to read these files and dump them into an HDFS (Cassandra, or another data source) which I can then query?...
0
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2answers
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Cassandra: capacity planning [duplicate]

Im investigating moving some large DBs from MySQL to Cassandra and Im trying to figure out how to plan the cluster. Historically, one would just buy disks to contain the relevant data but Im not clear ...
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3answers
2k views

Can't upgrade my Ubuntu server, it gets stuck on openjdk-6-jre-headless

I am using Ubuntu Server. When I do: apt-get upgrade it gets stuck on: Setting up openjdk-6-jre-headless (6b20-1.9.7-0ubuntu1) ... Why? And what can I do to stop it? I tried removing it with apt-...
2
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2answers
6k views

Cannot connect to my Cassandra

My Cassandra used to work with no problems. I was able to connect with no problems but now for some reason it doesn't work anymore. [default@unknown] connect localhost/9160; Exception connecting to ...