Cassandra Cloud

CassandraCloud is a tool that helps you configure Cassandra for clustered environments. It works well in Docker, EC2, and VirtualBox environments (and similar environments). It allows you to configure Cassandra easily. For example, it could be kicked off as a USER_DATA script in Amazon EC2 (AWS EC2). CassandraCloud usually runs once when an instance is first launched and then never again.

Config Overrides and Templates

CassandraCloud allows you to override values via OS ENVIRONMENT variables. There is an HCL config file, and there are command line arguments.

The HCL config file can be overridden with ENVIRONMENT which can be overridden with command line arguments.

CassandraCloud will generate ${CASSANDRA_HOME}/conf/cassandra.yaml file. You can specify a custom template (usually found in ${CASSANDRA_HOME}/conf/cassandra-yaml.template).

Example ${CASSANDRA_HOME}/conf/cassandra-yaml.template

cluster_name: ""

# Listen address for client communication
# Listen network interface for client communication

# Listen address for storage cluster communication
# Listen network interface for storage cluster communication

max_hints_delivery_threads: 16max_hints_delivery_threads: 2



To learn the complete syntax of the template this template syntax guide.

The above could generate a cassandra.yaml file as follows:


cluster_name: "My Cluster"
num_tokens: 32
storage_port: 7000
ssl_storage_port: 7001
native_transport_port: 9042
endpoint_snitch: SimpleSnitch

# Listen network interface for client communication
rpc_interface: localhost

# Listen network interface for storage cluster communication
listen_interface: localhost

max_hints_delivery_threads: 2

     - /opt/cassandra/data

commitlog_directory: /opt/cassandra/commitlog

    - class_name: org.apache.cassandra.locator.SimpleSeedProvider
          - seeds: ""

There are also templates for jvm.options,, and logback.xml.


./cassandra-cloud  -h
Usage of ./cassandra-cloud:
  -client-address string
        Client address for client driver communication. Example:, localhost, etc.
  -client-interface string
        Client address for client driver communication. Example: eth0, eth1, etc. (default "localhost")
  -cluster-address string
        Cluster address for inter-node communication. Example:, localhost, etc.
  -cluster-interface string
        Cluster interface for inter-node communication.  Example: eth0, eth1, etc. (default "localhost")
  -cluster-name string
        Name of the cluster (default "My Cluster")
  -cluster-seeds string
        Comma delimited list of initial clustrer contact points for bootstrapping (default "")
  -conf-yaml-template string
        Location of cassandra configuration template (default "/opt/cassandra/conf/cassandra-yaml.template")
  -config string
        Location of config file
  -data-dirs string
        Location of Cassandra Data directories
        Turn on debugging
        Prints out help information
  -snitch string
        Snitch type. Example: GossipingPropertyFileSnitch, PropertyFileSnitch, Ec2Snitch, etc. (default "SimpleSnitch")
  -v    Turns on verbose mode

Command line flag syntax:

-flag x  // non-boolean flags only


Cloud conf usually found in ${CASSANDRA_HOME}/conf/cloud.conf

# Defaults to false. Used for verbose mode.
# verbose = false

# Comma delimited list of seed hosts. Defaults to This is used for bootstrap only.
# Production clusters should have at least two seed servers.
# cluster_seeds =

# Cassandra home directory. Defaults to /opt/cassandra.
# home_dir = /opt/cassandra

# Are we supporting multiple DCs? Defaults to false.
# multi_dc = false

# Only one of these two can be set (defaults to address set to localhost Linux)
# cluster_address = localhost
# cluster_interface=eth1

# Only one of these two can be set (defaults to address set to localhost for OSX and interface set to eth0 for Linux)
# client_address=localhost
# client_interface=eth0

# Sets the snitch type for Cassandra. Defaults to simple snitch (for now).
# snitch=SimpleSnitch

# Sets up VNODE weight for servder. Defaults to 32 tokens per node
# num_tokens=32

# Location of template file. Defaults to /conf/cassandra-yaml.template
# conf_yaml_template = /opt/cassandra/conf/cassandra-yaml.template

# Location of cassandra config yaml file that we want to replace.
# Defaults to /conf/cassandra.yaml
# conf_yaml_file = /opt/cassandra/conf/cassandra.yaml

# Cluster port. Defaults to 7000.
# cluster_port = 7000
# Cluster SSL port. Defaults to 7001.
# cluster_ssl_port = 7001

# Client port. Defaults to 9042.
# client_port = 9042

# Data directories for Cassandra SSTables. Defaults to ["/opt/cassandra/data"]
# data_dirs = ["/opt/cassandra/data"]

Template variable (types, and how to override them)

The table below lists the variable names. A setting in the config file (Config Name) overrides the default value(Default Value). Environment Variables override config file settings (Config Name). Lastly values passed on the command line (Command line Args) override the config.

The Template Var Names are used by the templates.

For example the CommitLogDir template var can be used in a template by referring to it as ``.

Template Var Name Type Config Name Command line Args Environment Variable Default Value
Verbose bool verbose -verbose CASSANDRA_VERBOSE false
ClusterSeeds string cluster_seeds -cluster-seeds CASSANDRA_CLUSTER_SEEDS
CassandraHome string home_dir -home-dir CASSANDRA_HOME_DIR /opt/cassandra
MultiDataCenter bool multi_dc -multi-dc CASSANDRA_MULTI_DC false
DataDirs []string data_dirs -data-dirs CASSANDRA_DATA_DIRS [/opt/cassandra/data ]
CommitLogDir string commit_log_dir -commit-log-dir CASSANDRA_COMMIT_LOG_DIR /opt/cassandra/commitlog
ClusterListenAddress string cluster_address -cluster-address CASSANDRA_CLUSTER_ADDRESS localhost
ClusterListenInterface string cluster_interface -cluster-interface CASSANDRA_CLUSTER_INTERFACE  
ClientListenAddress string client_address -client-address CASSANDRA_CLIENT_ADDRESS localhost
ClientListenInterface string client_interface -client-interface CASSANDRA_CLIENT_INTERFACE  
Snitch string snitch -snitch CASSANDRA_SNITCH SimpleSnitch
ClusterName string cluster_name -cluster-name CASSANDRA_CLUSTER_NAME My Cluster
NumTokens int num_tokens -num-tokens CASSANDRA_NUM_TOKENS 32
CassandraConfigTemplate string conf_yaml_template -conf-yaml-template CASSANDRA_CONF_YAML_TEMPLATE /opt/cassandra/conf/cassandra-yaml.template
CassandraConfigFileName string conf_yaml_file -conf-yaml-file CASSANDRA_CONF_YAML_FILE /opt/cassandra/conf/cassandra.yaml
ClusterPort int cluster_port -cluster-port CASSANDRA_CLUSTER_PORT 7000
ClusterSslPort int cluster_ssl_port -cluster-ssl-port CASSANDRA_CLUSTER_SSL_PORT 7001
ClientPort int client_port -client-port CASSANDRA_CLIENT_PORT 9042

About us

Cloudurable provides AMIs, cloudformation templates and monitoring tools to support Cassandra in production running in EC2. We also teach advanced Cassandra courses which teaches how one could develop, support and deploy Cassandra to production in AWS EC2.

More details to follow