Connect to Cassandra using CQL shell within Kubernetes Cluster

These steps describe using the CQL shell (cqlsh) to connect to a deployed Apache Cassandra® 3.11.7 database from within a Kubernetes cluster.

Prerequisites

Create a Kubernetes cluster and deploy your database on the cluster.

To get started with a pre-built configuration, use the quickstart YAML files.
Install kubectl.
Point kubeconfig file or context to a Control Plane Kubernetes cluster.

Get credentials and start CQL shell within Kubernetes

On a local machine where you have authorized access to the Kubernetes cluster, use kubectl get secret to get the cluster1-superuser secret.

You must specify the cass-operator namespace as defined in the YAML configuration files.
```
kubectl get secret -o yaml cluster1-superuser -n cass-operator
```

In the output, get the encoded secret from the data.password field:

apiVersion: v1
data:
  password: <password-string>
  username: <user-name>
kind: Secret
metadata:
  creationTimestamp: "2021-05-04T23:55:23Z"
  name: cluster1-superuser
  namespace: cass-operator
  resourceVersion: "1479618"
  selfLink: /api/v1/namespaces/cass-operator/secrets/cluster1-superuser
  uid: <uid-string>
type: Opaque

Decode the secret.

This example assumes a macOS machine and uses base64 -d to decode the string.
```
echo '<password-string>' | base64 -d
```
The output is the decoded password string.

Use kubectl exec with your cass-operator namespace, the authenticated username (as defined in the YAML configuration files), the decoded password, and the path to cqlsh on the pod:

kubectl exec -n cass-operator -i -t -c cassandra cluster1-dc1-default-sts-0 -- /opt/cassandra/bin/cqlsh -u cluster1-superuser -p 'decoded-password'

If the connection succeeds, the output shows the cqlsh version and the cqlsh prompt.

Connected to cluster1 at 127.0.0.1:9042.
[cqlsh 5.0.1 | Cassandra 3.11.7 | CQL spec 3.4.4 | Native protocol v4]
Use HELP for help.
cluster1-superuser@cqlsh>

Submit DDL and DML commands to the connected Cassandra database

With the connection to cqlsh established inside the Kubernetes cluster, you can submit data definition language (DDL) and data manipulation language (DML) commands.

When cqlsh is running, the command prompt is prefixed with CLUSTER-USER@cqlsh>, such as cluster1-superuser@cqlsh>.

Create a keyspace.

You must specify the relevant datacenter name. In this example, as defined by the provided YAML, it is dc1.
```
CREATE KEYSPACE IF NOT EXISTS cycling WITH replication = { 'class' : 'NetworkTopologyStrategy', 'dc1' : '3' };
```

Define a table:

CREATE TABLE IF NOT EXISTS cycling.cyclist_semi_pro (
   id int,
   firstname text,
   lastname text,
   age int,
   affiliation text,
   country text,
   registration date,
   PRIMARY KEY (id));

Load some data:

INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (1, 'Carlos', 'Perotti', 22, 'Recco Club', 'ITA', '2020-01-12');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (2, 'Giovani', 'Pasi', 19, 'Venezia Velocità', 'ITA', '2016-05-15');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (3, 'Frances', 'Giardello', 24, 'Menaggio Campioni', 'ITA', '2018-07-29');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (4, 'Mark', 'Pastore', 19, 'Portofino Ciclisti', 'ITA', '2017-06-16');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (5, 'Irene', 'Cantona', 24, 'Como Velocità', 'ITA', '2012-07-22');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (6, 'Hugo', 'Herrera', 23, 'Bellagio Ciclisti', 'ITA', '2004-02-12');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (7, 'Marcel', 'Silva', 21, 'Paris Cyclistes', 'FRA', '2018-04-28');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (8, 'Theo', 'Bernat', 19, 'Nice Cavaliers', 'FRA', '2007-05-15');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (9, 'Richie', 'Draxler', 24, 'Normandy Club', 'FRA', '2011-02-26');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (10, 'Agnes', 'Cavani', 22, 'Chamonix Hauteurs', 'FRA', '2020-01-02');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (11, 'Pablo', 'Verratti', 19, 'Chamonix Hauteurs', 'FRA', '2006-05-15');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (12, 'Charles', 'Eppinger', 24, 'Chamonix Hauteurs', 'FRA', '2018-07-29');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (13, 'Stanley', 'Trout', 30, 'Bolder Boulder', 'USA', '2016-02-12');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (14, 'Juan', 'Perez', 31, 'Rutgers Alumni Riders', 'USA', '2017-06-16');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (15, 'Thomas', 'Fulton', 27, 'Exeter Academy', 'USA', '2012-12-15');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (16, 'Jenny', 'Hamler', 28, 'CU Alums Crankworkz', 'USA', '2012-07-22');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (17, 'Alice', 'McCaffrey', 26, 'Pennan Power', 'GBR', '2020-02-12');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (18, 'Nicholas', 'Burrow', 26, 'Aberdeen Association', 'GBR', '2016-02-12');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (19, 'Tyler', 'Higgins', 24, 'Highclere Agents', 'GBR', '2019-07-31');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (20, 'Leslie', 'Boyd', 18, 'London Cyclists', 'GBR', '2012-12-15');

Run a query:

SELECT * FROM cycling.cyclist_semi_pro;

Sample output:

 id | affiliation           | age | country | firstname | lastname  | registration
----+-----------------------+-----+---------+-----------+-----------+--------------
  5 |         Como Velocità |  24 |     ITA |     Irene |   Cantona |   2012-07-22
 10 |     Chamonix Hauteurs |  22 |     FRA |     Agnes |    Cavani |   2020-01-02
 16 |   CU Alums Crankworkz |  28 |     USA |     Jenny |    Hamler |   2012-07-22
 13 |        Bolder Boulder |  30 |     USA |   Stanley |     Trout |   2016-02-12
 11 |     Chamonix Hauteurs |  19 |     FRA |     Pablo |  Verratti |   2006-05-15
  1 |            Recco Club |  22 |     ITA |    Carlos |   Perotti |   2020-01-12
 19 |      Highclere Agents |  24 |     GBR |     Tyler |   Higgins |   2019-07-31
  8 |        Nice Cavaliers |  19 |     FRA |      Theo |    Bernat |   2007-05-15
  2 |      Venezia Velocità |  19 |     ITA |   Giovani |      Pasi |   2016-05-15
  4 |    Portofino Ciclisti |  19 |     ITA |      Mark |   Pastore |   2017-06-16
 18 |  Aberdeen Association |  26 |     GBR |  Nicholas |    Burrow |   2016-02-12
 15 |        Exeter Academy |  27 |     USA |    Thomas |    Fulton |   2012-12-15
 20 |       London Cyclists |  18 |     GBR |    Leslie |      Boyd |   2012-12-15
  7 |       Paris Cyclistes |  21 |     FRA |    Marcel |     Silva |   2018-04-28
  6 |     Bellagio Ciclisti |  23 |     ITA |      Hugo |   Herrera |   2004-02-12
  9 |         Normandy Club |  24 |     FRA |    Richie |   Draxler |   2011-02-26
 14 | Rutgers Alumni Riders |  31 |     USA |      Juan |     Perez |   2017-06-16
 17 |          Pennan Power |  26 |     GBR |     Alice | McCaffrey |   2020-02-12
 12 |     Chamonix Hauteurs |  24 |     FRA |   Charles |  Eppinger |   2018-07-29
  3 |     Menaggio Campioni |  24 |     ITA |   Frances | Giardello |   2018-07-29

Next steps

The Kubernetes Operator for Apache Cassandra and Cassandra are deployed to your Kubernetes cluster and you connected to cqlsh from within the Kubernetes cluster.

To learn how to connect to Apache Cassandra resources and applications that are inside the Kubernetes cluster from outside of the cluster, see Connect to Cassandra and apps from outside the Kubernetes cluster.

Connect to Cassandra using CQL shell within Kubernetes Cluster

Prerequisites

Get credentials and start CQL shell within Kubernetes

Submit DDL and DML commands to the connected Cassandra database

Next steps

Was this helpful?

Give Feedback