Questions tagged [cassandra]
Apache Cassandra is an open source distributed key-value database cluster, designed to scale linearly when adding nodes. It provides multi-datacenter replication.
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How to resolve a stuck major compaction in Apache Cassandra?
I've got a one-node Cassandra cluster which is currently stuck in a major compaction process. After executing a nodetool compactit started the compaction and I see the tmp-sstable files with a size of ...
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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 ...
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Cassandra: do more storage size, needs more CPU and RAM
I have gone through the recommended architecture of the Cassandra node configuration! according to which the recommended hardware infrastructure for the node is to have
RAM: 16-32 GB,
storage: 500GB -...
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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 ...
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Apache Cassandra Split Brain
Is it possible to put Apache Cassandra into a split-brain scenario where a network partitioned data service continues to run storing and accessing data without access to the full cluster?
If not, what ...
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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 ...
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How can I get Cassandra to automatically rebalance?
I am looking at a cassandra cluster, but the administration effort seems to be quite high. Is there any way I can configure Cassandra to rebalance nodes automically as new machines are added, some are ...
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Cassandra snapshot restoring : random missing data
I'm having a hard time restoring snapshot on Apache Cassandra (version 3.0.9). As far as I can say, I'm following the procedure described on datastax blog, along with several other ones (for instance :...
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How to achieve zero down time
For an application we want to achieve zero database and application down time using Active Active configuration. Our dB is Oracle
Following are my questions:
How can we achieve active active ...
Hiral Lakdavala
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Tunneling cassandra via ssh gives me a connection closed error
I have a server with two network interfaces. Cassandra is listening on a dedicated internal database network on eth1 (not accessable from outside). So I do my tunnel like this:
ssh -f -N -L9161:192....
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Cassandra: understanding replication factor
Hypothetical situation:
Setup a cassandra cluster with N nodes.
Create a keyspace and set replication_factor to 1 and use SimpleStrategy.
Add some data.
Remove 1 node.
Does this mean that 1/N of ...
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What is the best solution for backing up data in Cassandra? [closed]
What is the best solution for backing up data in Cassandra?
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Error When Starting Cassandra for First Time [closed]
I'm trying to get a single-node cluster of Cassandra set up on my VPS for a school project. So I installed cassandra on Ubuntu 16.04 (JVM 1.8.0_161), but when I run, I encounter this error... https://...
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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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Does nodetool repair repair the next node?
Let's assume we have a Cassandra cluster with the following ring: A -> B -> C -> D (no virtual nodes), and we assume that all the data is stored at RF=2. Now let's say that B dies, leaving us ...
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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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What is the best way to get a list of nodes that belong to a Cassandra cluster?
I'm creating some scripts for some Cassandra clusters I operate. Some of these scripts need a list of nodes that are part of the cluster.
nodetool status will print a list of the nodes and their ...
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How to authenticate with cassandra-stress 2.1
Is there a way to authenticate to cassandra using the new cassandra-stress tool released with cassandra 2.1? It appears as if the '-un' (username) and '-pw' (password) switches have been removed from ...
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"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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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 ...
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Cassandra tmpdir change location
Cassandra is failing to start if /tmp is set as noexec, which is pretty much default these days:
java.lang.NoClassDefFoundError: Could not initialize class com.sun.jna.Native
at org.apache....
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Cassandra EC2 slow response time
I have been developing with Cassandra locally for a while and response times on queries are in the region of 50ms.
I have set up a 5 node EC2 cluster from the cassandra community ami, everything went ...
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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 ...
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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 ...
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How to restrict Cassandra to use fixed memory
We are using Cassandra in order to collect data from Thingsboard. The memory it started with was 4GB (after executing the systemctl status for Cassandra) and after 15 hours it has reached up to 9.3GB. ...
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Cassandra ReadTimeout: code=1200 - Coordinator node timed out waiting for replica nodes
I've got 3 node cluster on DSE 4.8.8 with replication factor = 2 and consistency on write quorum and on read one. When I'm trying to select some of the data I get this error:
cqlsh:production> ...
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Operator \> and \< (string version comparison) are not recognised in shell script
I am trying to run Casandra nodetool and getting warnings coming from .sh script.
[root@d11ca4cc-fa95-c8a9-e133-e64c434f0e6f ~]# nodetool status
/opt/local/share/cassandra/bin/nodetool[53]: .[97]: [:...
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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 ...
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Is it better to generate "UUID" and "TIMESTAMP" within the NodeJS application or using the database built-in functions?
I am writing a TypeScript-NodeJS application and want to handle object ids and created_at TIMESTAMP within the NodeJS application, instead of using MySQL or Cassandra built-in UUID or TIMESTAMP ...
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datastax-agent Cannot connect Error
Seeing an issue with the Opscenter Agents. Opscenter reports the agents are not connected and in the agent.log on each node, they all report the following:
com.datastax.driver.core.exceptions....
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DataStax OpsCenter agent fails to start when Cassandra requires authentication
Problem
I can not get OpsCenter get to connect to datastax-agent. It seems that datastax-agent starts and tries to connect to cassandra, fails because it does not know the correct credentials, but it ...
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cassandra nodetool repair - how to schedule properly?
Im putting together a 16 node cassandra cluster (replication factor 2) and want to setup a schedule for nodetool repair. gc_grace_seconds is at the default.
Two questions:
My first impulse is to ...
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Cassandra 2.x - cluster does not rebalance after adding new nodes
I had 3 nodes, all with ~550GB, and added 4 more. I hoped that data would migrate on its own from old servers to new ones. Unfortunately after one day, data seems to stay in old places.
In parallel, ...
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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 in ...
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Which version of the JDK should we install for Cassandra 4.0.1
We are planning to upgrade our Cassandra servers from 3.0.11 to 4.0.1
Here it says to use JDK 8. I would like to know if as of this writing this is still the case. I believe the latest released Oracle ...
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Mesos slave IP for Marathon-launched ( docker container ) service instance
i have a docker image i would like to launch a couple instances of via Mesos/Marathon.
i'm using BRIDGE networking in docker, and i would like to pass in the "public" ( i.e. not the container's ...
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Incredibly high load average on a Centos server
I have a Centos 6.4 server that's being used as a Cassandra node in a production environment, it is still working and responding to queries etc, but the load average is rather "high" a.k.a. buggy? In ...
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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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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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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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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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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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IP address resolution in Cassandra MultiDC setup
We have a scenario for which we are considering using apache Cassandra for deployment for our data storage needs.The setup is to be spread across multiple data centers in different regions(physical ...
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Monitoring Cassandra Server Logs?
I've done some searching and have not found any examples of people using something like FluentD to forward Cassandra log file data (system.log) to a log indexer.
Is this something any is doing? If ...
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Cassandra nodetool repair failure - broken pipe
we're trying to check our Cassandra cluster data integrity with:
nodetool repair
but after several minutes (~2-10min), we got strange connection resets / broken pipe
stack trace on a first node:
...
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Can I run multiple nodes of Cassandra on my mac without a virtual machine for each?
You can see in the doco here that setting up each instance of Cassandra requires a new 'node'.
My question is - to run a cluster with multiple nodes of Cassandra on my Mac (Running Mavericks) - do I ...
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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 ...
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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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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....
user44468
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Cassandra nodes disk space usage above 90%
Hi I'm running a 5 node dse cassandra cluster. Every node is about 90 % disk usage ,so I've deleted data from my keyspace(I've only one keyspace).but my disk space is still 90 % .Is there anyway to ...
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