Cassandra, or Apache Cassandra, is a highly scalable open source database system, achieving great performance on multi-node setups. In this tutorial, you’ll learn how to install Cassandra, the Oracle Java VM, which is highly recommended for Cassandra, and how to run your first test single-node cluster.
Make a temporary folder on your home directory to install Java.
mkdir ~/temp cd ~/temp
The Cassandra documentation highly recommends the Oracle Java VM 8, so you’ll have to download it from Oracle’s website. It requires a free account, which you can register here. After you’ve created your account, download either the 32-bit or the 64-bit (recommended) version of Java 8. Once you’ve downloaded it, transfer it to your VPS using FTP or any other tool. You can find a tutorial on how to setup an FTP server here.
Now extract the contents of the archive:
tar -zxf jdk-8u65-linux-x64.tar.gz
You should now move it to the proper folder:
sudo mkdir /usr/local/java sudo mv jdk1.8.0_65/ /usr/local/java
To make it the default Java VM on your VPS, add these lines to the /etc/profile file:
JAVA_HOME=/usr/local/java/jdk1.8.0_65 PATH=$PATH:$HOME/bin:$JAVA_HOME/bin JRE_HOME=/usr/local/java/jdk1.8.0_65 PATH=$PATH:$HOME/bin:$JRE_HOME/bin export JAVA_HOME export JRE_HOME export PATH
by scrolling down after running:
sudo nano /etc/profile
and pasting it at the end of the file, like so:
After you’ve done this, press CTRL+O to save and CTRL+X to exit. Next, run the following lines so when the command “java” is called, it’s done so by the right VM.
sudo update-alternatives --install "/usr/bin/java" "java" "/usr/local/java/jdk1.8.0_65/bin/java" 1 sudo update-alternatives --install "/usr/bin/javac" "javac" "/usr/local/java/jdk1.8.0_65/bin/javac" 1 sudo update-alternatives --install "/usr/bin/javaws" "javaws" "/usr/local/java/jdk1.8.0_65/bin/javaws" 1 sudo update-alternatives --set java /usr/local/java/jdk1.8.0_65/bin/java sudo update-alternatives --set javac /usr/local/java/jdk1.8.0_65/bin/javac sudo update-alternatives --set javaws /usr/local/java/jdk1.8.0_65/bin/javaws
You should now reboot your VPS so everything is updated:
When establishing a SSH connection again, test to see if everything is set properly by running:
java -version echo $JAVA_HOME
If everything went OK, you should see this:
To install Cassandra, download the binary files from the website, unpack them and move it to your personal folder:
cd ~/temp wget http://mirror.cc.columbia.edu/pub/software/apache/cassandra/2.2.3/apache-cassandra-2.2.3-bin.tar.gz tar -zxf apache-cassandra-2.2.3-bin.tar.gz mv apache-cassandra-2.2.3 ~/cassandra
Next, make sure that the folders Cassandra accesses, such as the log folder, exists and that Cassandra has the right to write on it:
sudo mkdir /var/lib/cassandra sudo mkdir /var/log/cassandra sudo chown -R $USER:$GROUP /var/lib/cassandra sudo chown -R $USER:$GROUP /var/log/cassandra
Now set Cassandra’s variables by running:
export CASSANDRA_HOME=~/cassandra export PATH=$PATH:$CASSANDRA_HOME/bin
To run a single-node test cluster of Cassandra, you aren’t going to need to change anything on the cassandra.yaml file. Simply run:
sudo sh ~/cassandra/bin/cassandra
and then run:
sudo sh ~/cassandra/bin/cqlsh
and if it says "Connected to: 'Test Cluster'" as it does below, you are now running your single-node cluster.
root@cassandra:~# sudo sh ~/cassandra/bin/cqlsh Connected to Test Cluster at 127.0.0.1:9042. [cqlsh 5.0.1 | Cassandra 2.2.3 | CQL spec 3.3.1 | Native protocol v4] Use HELP for help. cqlsh>
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