How To Setup Multi Node Cassandra 2 Cluster

This is going to be step by step guide how to install multi node Cassandra 2 cluster on Ubuntu server.

In this guide we are going to setup 5 nodes cluster. Bellow is the list of my machines in the cluster and obviously you may have different IPs.

• 10.64.200.47
• 10.64.200.48
• 10.64.200.49
• 10.64.200.50
• 10.64.200.51

➤ Step 1 is to have Java 7 or Java 8 installed in all nodes.

Let’s install Java 8 by adding custom apt repository.

	sudo add-apt-repository ppa:webupd8team/java
	sudo apt-get update
	sudo apt-get install oracle-java8-installer
	java -version
	sudo apt-get install oracle-java8-set-default

➤ Step 2 is to add system group and user for cassandra in all nodes.

	sudo addgroup cassandra
	sudo adduser --ingroup cassandra cassandra
	sudo adduser cassandra sudo

➤ Step 3 is to download and extract cassandra package in all nodes.

	sudo su - cassandra
	wget http://mirrors.ae-online.de/apache/cassandra/2.1.3/apache-cassandra-2.1.3-bin.tar.gz
	sudo tar -xvf /home/cassandra/apache-cassandra-2.1.3-bin.tar.gz -C /usr/local/
	cd /usr/local/
	sudo mv apache-cassandra-2.1.3 cassandra-2.1.3
	sudo ln -s /usr/local/cassandra-2.1.3 /usr/local/cassandra
	sudo chown -R cassandra:cassandra /usr/local/cassandra-2.1.3

➤ Step 4 is to configure environment variables in all nodes.

Just edit the .profile file vim ~/.profile and paste the following at the end of the file:

	export JAVA_HOME=$(readlink -f /usr/bin/java | sed "s:bin/java::")
	export CASSANDRA_INSTALL=/usr/local/cassandra
	export CASSANDRA_HOME=$CASSANDRA_INSTALL

Afterwards source the .profile file source ~/.profile.

➤ Step 5 is to configure cassandra instances in all nodes

Just edit the $CASSANDRA_HOME/conf/cassandra.yaml file vim $CASSANDRA_HOME/conf/cassandra.yaml and replace the following keys with proper values:

	cluster_name: 'MyFirstCluster'
	seeds: "10.64.200.47, 10.64.200.48"
	listen_address: 10.64.200.47
	rpc_address: 10.64.200.47

* Note that each node should have it’s own listen_address and rpc_address corresponding to it’s IP address.

That’s it we are done with configuration!

➤ Step 6 is to start the cluster and verify it.

First seed nodes should be started so they can serve as seeds for others. To start the node simply run the following:

$CASSANDRA_HOME/bin/cassandra -f

To verify after all nodes are started run the following command:

$CASSANDRA_HOME/bin/nodetool status

You should see something like the following:

	Datacenter: datacenter1
	=======================
	Status=Up/Down
	|/ State=Normal/Leaving/Joining/Moving
	-- Address Load Tokens Owns Host ID Rack
	UN 10.64.200.47 122.04 KB 256 ? e66d39d0-80d3-492f-900a-5dd006d9a763 rack1
	UN 10.64.200.48 142.04 KB 256 ? e97a6709-3216-43af-90de-5a3017761a46 rack1
	UN 10.64.200.49 127.83 KB 256 ? 6f74e3f8-4f20-43d8-90ff-5439939f5159 rack1
	UN 10.64.200.50 137.89 KB 256 ? 8bd7390d-dde8-4aaa-8a44-73981e698a05 rack1
	UN 10.64.200.51 161.07 KB 256 ? cf967b8c-4187-46d3-a464-fff09c28bb0d rack1

➤ Step 7 is to execute simple CQL.

To connect to cassandra cluster run the following command from any machine which has cassandra binaries:

$CASSANDRA_HOME/bin/cqlsh 10.64.200.49 9042

And run the following examples:

	CREATE KEYSPACE "testdb" WITH REPLICATION = { 'class' : 'SimpleStrategy' , 'replication_factor' :3 };
	USE testdb;
	CREATE TABLE employee (
	employeeID int,
	departmentID int,
	firstName varchar,
	lastName varchar,
	PRIMARY KEY (employeeID, departmentID)
	);
	INSERT INTO employee (employeeID, departmentID, firstName, lastName)
	VALUES (120, 10, 'John', 'Green');
	INSERT INTO employee (employeeID, departmentID, firstName, lastName)
	VALUES (125, 13, 'Arthur', 'Smith');
	SELECT * FROM employee WHERE employeeID IN (120, 125);
	SELECT COUNT(*) FROM employee;
	CREATE INDEX employee_firstName_idx ON employee(firstName);
	SELECT * FROM employee WHERE firstName = 'Arthur';