You are looking at the documentation of a prior release. To read the documentation of the latest release, please
visit here.
New to KubeDB? Please start here.
Elasticsearch Topology
KubeDB Elasticsearch supports multi-node database cluster.
Before You Begin
At first, you need to have a Kubernetes cluster, and the kubectl command-line tool must be configured to communicate with your cluster. If you do not already have a cluster, you can create one by using minikube.
Now, install KubeDB cli on your workstation and KubeDB operator in your cluster following the steps here.
To keep things isolated, this tutorial uses a separate namespace called demo
throughout this tutorial.
$ kubectl create ns demo
namespace/demo created
$ kubectl get ns demo
NAME STATUS AGE
demo Active 5s
Note: YAML files used in this tutorial are stored in docs/examples/elasticsearch folder in GitHub repository kubedb/docs.
Create multi-node Elasticsearch
Elasticsearch can be created with multiple nodes. If you want to create an Elasticsearch cluster with three nodes, you need to set spec.replicas
to 3
. In this case, all of these three nodes will act as master, data and client.
Check following Elasticsearch object
apiVersion: kubedb.com/v1alpha1
kind: Elasticsearch
metadata:
name: multi-node-es
namespace: demo
spec:
version: "6.3-v1"
replicas: 3
storageType: Durable
storage:
storageClassName: "standard"
accessModes:
- ReadWriteOnce
resources:
requests:
storage: 1Gi
Here,
spec.replicas
is the number of nodes in the Elasticsearch cluster. Here, we are creating a three node Elasticsearch cluster.
Note: If
spec.topology
is set, you won’t able tospec.replicas
. KubeDB will reject the create request for Elasticsearch crd from validating webhook.
Create example above with following command
$ kubectl create -f https://github.com/kubedb/docs/raw/v0.13.0-rc.0/docs/examples/elasticsearch/clustering/multi-node-es.yaml
elasticsearch.kubedb.com/multi-node-es created
Let’s describe Elasticsearch object multi-node-es
while Running
$ kubedb describe es -n demo multi-node-es
Name: multi-node-es
Namespace: demo
CreationTimestamp: Fri, 05 Oct 2018 12:51:43 +0600
Labels: <none>
Annotations: kubectl.kubernetes.io/last-applied-configuration={"apiVersion":"kubedb.com/v1alpha1","kind":"Elasticsearch","metadata":{"annotations":{},"name":"multi-node-es","namespace":"demo"},"spec":{"replicas":3...
Status: Running
Replicas: 3 total
StorageType: Durable
Volume:
StorageClass: standard
Capacity: 1Gi
Access Modes: RWO
StatefulSet:
Name: multi-node-es
CreationTimestamp: Fri, 05 Oct 2018 12:51:45 +0600
Labels: kubedb.com/kind=Elasticsearch
kubedb.com/name=multi-node-es
node.role.client=set
node.role.data=set
node.role.master=set
Annotations: <none>
Replicas: 824639906344 desired | 3 total
Pods Status: 3 Running / 0 Waiting / 0 Succeeded / 0 Failed
Service:
Name: multi-node-es
Labels: kubedb.com/kind=Elasticsearch
kubedb.com/name=multi-node-es
Annotations: <none>
Type: ClusterIP
IP: 10.101.96.68
Port: http 9200/TCP
TargetPort: http/TCP
Endpoints: 192.168.1.18:9200,192.168.1.19:9200,192.168.1.20:9200
Service:
Name: multi-node-es-master
Labels: kubedb.com/kind=Elasticsearch
kubedb.com/name=multi-node-es
Annotations: <none>
Type: ClusterIP
IP: 10.103.195.123
Port: transport 9300/TCP
TargetPort: transport/TCP
Endpoints: 192.168.1.18:9300,192.168.1.19:9300,192.168.1.20:9300
Database Secret:
Name: multi-node-es-auth
Labels: kubedb.com/kind=Elasticsearch
kubedb.com/name=multi-node-es
Annotations: <none>
Type: Opaque
Data
====
ADMIN_USERNAME: 5 bytes
READALL_USERNAME: 7 bytes
sg_action_groups.yml: 430 bytes
sg_roles.yml: 312 bytes
ADMIN_PASSWORD: 8 bytes
READALL_PASSWORD: 8 bytes
sg_config.yml: 242 bytes
sg_internal_users.yml: 156 bytes
sg_roles_mapping.yml: 73 bytes
Certificate Secret:
Name: multi-node-es-cert
Labels: kubedb.com/kind=Elasticsearch
kubedb.com/name=multi-node-es
Annotations: <none>
Type: Opaque
Data
====
key_pass: 6 bytes
node.jks: 3009 bytes
root.jks: 864 bytes
sgadmin.jks: 3010 bytes
Topology:
Type Pod StartTime Phase
---- --- --------- -----
master|client|data multi-node-es-0 2018-10-05 12:51:46 +0600 +06 Running
client|data|master multi-node-es-1 2018-10-05 12:52:03 +0600 +06 Running
master|client|data multi-node-es-2 2018-10-05 12:52:33 +0600 +06 Running
No Snapshots.
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal Successful 4m Elasticsearch operator Successfully created Service
Normal Successful 4m Elasticsearch operator Successfully created Service
Normal Successful 2m Elasticsearch operator Successfully created StatefulSet
Normal Successful 2m Elasticsearch operator Successfully created Elasticsearch
Normal Successful 2m Elasticsearch operator Successfully patched StatefulSet
Normal Successful 1m Elasticsearch operator Successfully patched Elasticsearch
Normal Successful 1m Elasticsearch operator Successfully patched StatefulSet
Normal Successful 1m Elasticsearch operator Successfully patched Elasticsearch
Here, we can see in Topology
section that all three Pods are acting as master, data and client.
Create Elasticsearch with dedicated node
If you want to use separate node for master, data and client role, you need to configure spec.topology
field of Elasticsearch crd.
In this tutorial, we will create following Elasticsearch with topology
apiVersion: kubedb.com/v1alpha1
kind: Elasticsearch
metadata:
name: topology-es
namespace: demo
spec:
version: "6.3-v1"
storageType: Durable
topology:
master:
prefix: master
replicas: 1
storage:
storageClassName: "standard"
accessModes:
- ReadWriteOnce
resources:
requests:
storage: 1Gi
data:
prefix: data
replicas: 2
storage:
storageClassName: "standard"
accessModes:
- ReadWriteOnce
resources:
requests:
storage: 1Gi
client:
prefix: client
replicas: 2
storage:
storageClassName: "standard"
accessModes:
- ReadWriteOnce
resources:
requests:
storage: 1Gi
Here,
spec.topology
point to the number of pods we want as dedicatedmaster
,client
anddata
nodes and also specify prefix, storage, resources for the pods.
Let’s create this Elasticsearch object
$ kubectl create -f https://github.com/kubedb/docs/raw/v0.13.0-rc.0/docs/examples/elasticsearch/clustering/topology-es.yaml
elasticsearch.kubedb.com/topology-es created
When this object is created, Elasticsearch database has started with 5 pods under 3 different StatefulSets.
$ kubectl get statefulset -n demo --show-labels --selector="kubedb.com/kind=Elasticsearch,kubedb.com/name=topology-es"
NAME DESIRED CURRENT AGE LABELS
client-topology-es 2 2 1m kubedb.com/kind=Elasticsearch,kubedb.com/name=topology-es,node.role.client=set
data-topology-es 2 2 48s kubedb.com/kind=Elasticsearch,kubedb.com/name=topology-es,node.role.data=set
master-topology-es 1 1 1m kubedb.com/kind=Elasticsearch,kubedb.com/name=topology-es,node.role.master=set
Three StatefulSets are created for client, data and master node respectively.
client-topology-es
spec: topology: client: prefix: client replicas: 2 storage: storageClassName: "standard" accessModes: - ReadWriteOnce resources: requests: storage: 1Gi
This configuration creates a StatefulSet named
client-topology-es
for client nodespec.replicas
is set to2
. Two dedicated nodes is created as client.- Label
node.role.client: set
is added in Pods - Each Pod will receive a single PersistentVolume with a StorageClass of standard and 1Gi of provisioned storage.
data-topology-es
spec: topology: data: prefix: data replicas: 2 storage: storageClassName: "standard" accessModes: - ReadWriteOnce resources: requests: storage: 1Gi
This configuration creates a StatefulSet named
data-topology-es
for data node.spec.replicas
is set to2
. Two dedicated nodes is created for data.- Label
node.role.data: set
is added in Pods - Each Pod will receive a single PersistentVolume with a StorageClass of standard and 1 Gib of provisioned storage.
master-topology-es
spec: topology: master: prefix: master replicas: 1 storage: storageClassName: "standard" accessModes: - ReadWriteOnce resources: requests: storage: 1Gi
This configuration creates a StatefulSet named
data-topology-es
for master nodespec.replicas
is set to1
. One dedicated node is created as master.- Label
node.role.master: set
is added in Pods - Each Pod will receive a single PersistentVolume with a StorageClass of standard and 1Gi of provisioned storage.
Note: StatefulSet name format:
{topology-prefix}-{elasticsearch-name}
Let’s describe this Elasticsearch
$ kubedb describe es -n demo topology-es
Name: topology-es
Namespace: demo
CreationTimestamp: Fri, 05 Oct 2018 14:40:24 +0600
Labels: <none>
Annotations: kubectl.kubernetes.io/last-applied-configuration={"apiVersion":"kubedb.com/v1alpha1","kind":"Elasticsearch","metadata":{"annotations":{},"name":"topology-es","namespace":"demo"},"spec":{"storageType":...
Status: Creating
StorageType: Durable
No volumes.
StatefulSet:
Name: client-topology-es
CreationTimestamp: Fri, 05 Oct 2018 14:40:26 +0600
Labels: kubedb.com/kind=Elasticsearch
kubedb.com/name=topology-es
node.role.client=set
Annotations: <none>
Replicas: 824640231228 desired | 2 total
Pods Status: 2 Running / 0 Waiting / 0 Succeeded / 0 Failed
StatefulSet:
Name: data-topology-es
CreationTimestamp: Fri, 05 Oct 2018 14:41:21 +0600
Labels: kubedb.com/kind=Elasticsearch
kubedb.com/name=topology-es
node.role.data=set
Annotations: <none>
Replicas: 824640232652 desired | 2 total
Pods Status: 2 Running / 0 Waiting / 0 Succeeded / 0 Failed
StatefulSet:
Name: master-topology-es
CreationTimestamp: Fri, 05 Oct 2018 14:41:00 +0600
Labels: kubedb.com/kind=Elasticsearch
kubedb.com/name=topology-es
node.role.master=set
Annotations: <none>
Replicas: 824641372604 desired | 1 total
Pods Status: 1 Running / 0 Waiting / 0 Succeeded / 0 Failed
Service:
Name: topology-es
Labels: kubedb.com/kind=Elasticsearch
kubedb.com/name=topology-es
Annotations: <none>
Type: ClusterIP
IP: 10.98.164.122
Port: http 9200/TCP
TargetPort: http/TCP
Endpoints: 192.168.1.26:9200,192.168.1.27:9200
Service:
Name: topology-es-master
Labels: kubedb.com/kind=Elasticsearch
kubedb.com/name=topology-es
Annotations: <none>
Type: ClusterIP
IP: 10.111.168.40
Port: transport 9300/TCP
TargetPort: transport/TCP
Endpoints: 192.168.1.28:9300
Database Secret:
Name: topology-es-auth
Labels: kubedb.com/kind=Elasticsearch
kubedb.com/name=topology-es
Annotations: <none>
Type: Opaque
Data
====
ADMIN_USERNAME: 5 bytes
READALL_PASSWORD: 8 bytes
sg_internal_users.yml: 156 bytes
ADMIN_PASSWORD: 8 bytes
READALL_USERNAME: 7 bytes
sg_action_groups.yml: 430 bytes
sg_config.yml: 242 bytes
sg_roles.yml: 312 bytes
sg_roles_mapping.yml: 73 bytes
Certificate Secret:
Name: topology-es-cert
Labels: kubedb.com/kind=Elasticsearch
kubedb.com/name=topology-es
Annotations: <none>
Type: Opaque
Data
====
key_pass: 6 bytes
node.jks: 3008 bytes
root.jks: 864 bytes
sgadmin.jks: 3010 bytes
Topology:
Type Pod StartTime Phase
---- --- --------- -----
client client-topology-es-0 2018-10-05 14:40:27 +0600 +06 Running
client client-topology-es-1 2018-10-05 14:40:44 +0600 +06 Running
data data-topology-es-0 2018-10-05 14:41:22 +0600 +06 Running
data data-topology-es-1 2018-10-05 14:41:49 +0600 +06 Running
master master-topology-es-0 2018-10-05 14:41:01 +0600 +06 Running
No Snapshots.
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal Successful 2m Elasticsearch operator Successfully created Service
Normal Successful 2m Elasticsearch operator Successfully created Service
Normal Successful 1m Elasticsearch operator Successfully created StatefulSet
Normal Successful 1m Elasticsearch operator Successfully created StatefulSet
Normal Successful 18s Elasticsearch operator Successfully created StatefulSet
Here, we can see from Topology
section that 2 pods working as client, 2 pods working as data and 1 pod working as master.
Two services are also created for this Elasticsearch object.
- Service
quick-elasticsearch
targets all Pods which are acting as client node - Service
quick-elasticsearch-master
targets all Pods which are acting as master node
Cleaning up
To cleanup the Kubernetes resources created by this tutorial, run:
$ kubectl patch -n demo es/multi-node-es es/topology-es -p '{"spec":{"terminationPolicy": "WipeOut"}}' --type="merge"
$ kubectl delete -n demo es/multi-node-es es/topology-es
$ kubectl delete ns demo
Next Steps
- Learn about taking instant backup of Elasticsearch database using KubeDB.
- Learn how to schedule backup of Elasticsearch database.
- Learn about initializing Elasticsearch with Snapshot.
- Monitor your Elasticsearch database with KubeDB using
out-of-the-box
builtin-Prometheus. - Monitor your Elasticsearch database with KubeDB using
out-of-the-box
CoreOS Prometheus Operator. - Detail concepts of Elasticsearch object.
- Detail concepts of Snapshot object.
- Use private Docker registry to deploy Elasticsearch with KubeDB.
- Want to hack on KubeDB? Check our contribution guidelines.