Cassandra

Managed Apache Cassandra: a wide-column distributed database with single-node or multi-node high-availability rings.

Creating a Cassandra instance

From the StackBlaze dashboard, click New service, then Database, then Cassandra. Pick a plan and storage size, and StackBlaze provisions the instance for you.

Connecting a Cassandra instance to a service injects the CASSANDRA_CONTACT_POINTS environment variable into that service. Your application reads the contact points from this variable, and the driver connects to them on the CQL port. There is nothing to hardcode.

Connecting

Cassandra uses the CQL binary protocol on port 9042. Services in the same project reach the database over the cluster's private network using its internal contact point. The internal address takes the form below:

[service-name].internal:9042

Connect using a CQL driver for your language, or the cqlsh command line shell pointed at the same contact point and port.

Standard vs high availability

You choose between Standard and high availability when creating the instance. Standard runs a single node, which is a great fit for development and lower-stakes workloads. High availability runs a multi-node ring with a tunable replication factor and consistency level, so data is replicated across nodes and the cluster stays available during a node loss.

Connecting from Python

Install the cassandra-driver package, read the contact points from CASSANDRA_CONTACT_POINTS, and connect on the CQL port:

import os
from cassandra.cluster import Cluster

contact_points = os.environ["CASSANDRA_CONTACT_POINTS"].split(",")
cluster = Cluster(contact_points, port=9042)
session = cluster.connect()

session.execute(
    "CREATE KEYSPACE IF NOT EXISTS app "
    "WITH replication = {'class': 'SimpleStrategy', 'replication_factor': 1}"
)
session.set_keyspace("app")

session.execute(
    "CREATE TABLE IF NOT EXISTS users (id uuid PRIMARY KEY, name text)"
)

rows = session.execute("SELECT release_version FROM system.local")
print(rows.one().release_version)

cluster.shutdown()

Backups

StackBlaze takes automated, encrypted backups that follow the platform backup policy applied to all managed databases. For details on schedules, restores, and how the policy works, see /docs/databases/backups.