natarajan77 / cassandra-1

Deploying Clustered Cassandra on OpenShift

cassandra

Deploying Clustered Cassandra on OpenShift

Manual method (OpenShift versions prior to v3.7)

oc new-project cassandra

As cluster admin, make the following policy change:

oc adm policy add-scc-to-user anyuid -z default -n cassandra

Create (3) apps. Wait for each pod to become ready before creating the next app.

oc new-app --name=cassandra-0 docker.io/cassandra -e CASSANDRA_BROADCAST_ADDRESS=cassandra-0.cassandra.svc.cluster.local

oc new-app --name=cassandra-1 docker.io/cassandra -e CASSANDRA_SEEDS=cassandra-0.cassandra.svc.cluster.local CASSANDRA_BROADCAST_ADDRESS=cassandra-1.cassandra.svc.cluster.local

oc new-app --name=cassandra-2 docker.io/cassandra -e CASSANDRA_SEEDS=cassandra-0.cassandra.svc.cluster.local CASSANDRA_BROADCAST_ADDRESS=cassandra-2.cassandra.svc.cluster.local

Proceed to checking the cluster status.

StatefulSets method (tech preview in v3.7)

Based on an example from the Kubernetes tutorials.

(3) existing 1Gi PVs are required.

Create a project

oc new-project statefuldead

As cluster admin, make the following policy change:

oc adm policy add-scc-to-user privileged -z default -n statefuldead

Create the Service and StatefulSet from a template.

oc process -f https://raw.githubusercontent.com/bkoz/cassandra/master/cassandra-cluster.yaml | oc create -f -

Check the cluster status by running nodetool status from any pod that is ready.

Wait for (3) cassandra pods to become ready.

oc get pods

NAME          READY     STATUS    RESTARTS   AGE
cassandra-0   1/1       Running   0          1h
cassandra-1   1/1       Running   0          59m
cassandra-2   1/1       Running   0          58m

oc rsh cassandra-0 nodetool status

Datacenter: DC1-K8Demo
======================
Status=Up/Down
|/ State=Normal/Leaving/Joining/Moving
--  Address      Load       Tokens       Owns (effective)  Host ID                               Rack
UN  172.17.0.9   83.54 KiB  32           63.0%             68fc41fd-3d3f-435a-bbd4-50e9869ba0ba  Rack1-K8Demo
UN  172.17.0.8   127.51 KiB  32           61.0%             81d63634-7161-4042-8f4e-c0aaff465f16  Rack1-K8Demo
UN  172.17.0.10  84.71 KiB  32           75.9%             68489417-2864-4a42-9897-e31433265407  Rack1-K8Demo

Clean up

oc delete all,pvc --all