Kubernetes Nacos

This project contains a Nacos Docker image meant to facilitate the deployment of Nacos on Kubernetes via StatefulSets.

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Quick Start

• Clone Project

git clone https://github.com/nacos-group/nacos-k8s.git

• Simple Start

If you want to start Nacos without NFS, but emptyDirs will possibly result in a loss of data. as follows:

cd nacos-k8s
chmod +x quick-startup.sh
./quick-startup.sh

• Testing

  • Service registration

  curl -X PUT 'http://cluster-ip:8848/nacos/v1/ns/instance?serviceName=nacos.naming.serviceName&ip=20.18.7.10&port=8080'

  • Service discovery

  curl -X GET 'http://cluster-ip:8848/nacos/v1/ns/instances?serviceName=nacos.naming.serviceName'

  • Publish config

  curl -X POST "http://cluster-ip:8848/nacos/v1/cs/configs?dataId=nacos.cfg.dataId&group=test&content=helloWorld"

  • Get config

  curl -X GET "http://cluster-ip:8848/nacos/v1/cs/configs?dataId=nacos.cfg.dataId&group=test"

Advanced

In advanced use, the cluster is automatically scaled and data is persisted, but PersistentVolumeClaims must be deployed. In this example, NFS is used.

Deploy NFS

• Create Role

kubectl create -f deploy/nfs/rbac.yaml

If your K8S namespace is not default, execute the following script before creating RBAC

# Set the subject of the RBAC objects to the current namespace where the provisioner is being deployed
$ NS=$(kubectl config get-contexts|grep -e "^\*" |awk '{print $5}')
$ NAMESPACE=${NS:-default}
$ sed -i'' "s/namespace:.*/namespace: $NAMESPACE/g" ./deploy/nfs/rbac.yaml

• Create ServiceAccount And deploy NFS-Client Provisioner

kubectl create -f deploy/nfs/deployment.yaml

• Create NFS StorageClass

kubectl create -f deploy/nfs/class.yaml

• Verify that NFS is working

kubectl get pod -l app=nfs-client-provisioner

Deploy database

• Deploy master

cd nacos-k8s

kubectl create -f deploy/mysql/mysql-master-nfs.yaml

• Deploy slave

cd nacos-k8s 

kubectl create -f deploy/mysql/mysql-slave-nfs.yaml

• Verify that Database is working

# master
kubectl get pod 
NAME                         READY   STATUS    RESTARTS   AGE
mysql-master-gf2vd                        1/1     Running   0          111m

# slave
kubectl get pod 
mysql-slave-kf9cb                         1/1     Running   0          110m

Deploy Nacos

• Modify depoly/nacos/nacos-pvc-nfs.yaml

data:
  mysql.master.db.name: "db name"
  mysql.master.port: "master db port"
  mysql.slave.port: "slave db port"
  mysql.master.user: "master db username"
  mysql.master.password: "master db password"

• Create Nacos

kubectl create -f nacos-k8s/deploy/nacos/nacos-pvc-nfs.yaml

• Verify that Nacos is working

kubectl get pod -l app=nacos


NAME      READY   STATUS    RESTARTS   AGE
nacos-0   1/1     Running   0          19h
nacos-1   1/1     Running   0          19h
nacos-2   1/1     Running   0          19h

Scale Testing

• Use kubectl exec to get the cluster config of the Pods in the nacos StatefulSet.

for i in 0 1; do echo nacos-$i; kubectl exec nacos-$i cat conf/cluster.conf; done

The StatefulSet controller provides each Pod with a unique hostname based on its ordinal index. The hostnames take the form of <statefulset name>-<ordinal index>. Because the replicas field of the nacos StatefulSet is set to 2, In the cluster file only two nacos address

• Use kubectl to scale StatefulSets

kubectl scale sts nacos --replicas=3

• Use kubectl exec to get the cluster config of the Pods in the nacos StatefulSet after scale StatefulSets

for i in 0 1 2; do echo nacos-$i; kubectl exec nacos-$i cat conf/cluster.conf; done

• Use kubectl exec to get the state of the Pods in the nacos StatefulSet after scale StatefulSets

for i in 0 1 2; do echo nacos-$i; kubectl exec nacos-$i curl GET "http://localhost:8848/nacos/v1/ns/raft/state"; done

You can find that the new node has joined the cluster

Prerequisites

• Kubernetes Node configuration(for reference only)

Hostname	Configuration
k8s-master	CentOS Linux release 7.4.1708 (Core) Single-core processor Mem 4G Cloud disk 40G
node01	CentOS Linux release 7.4.1708 (Core) Single-core processor Mem 4G Cloud disk 40G
node02	CentOS Linux release 7.4.1708 (Core) Single-core processor Mem 4G Cloud disk 40G

• Kubernetes version：1.12.2+
• NFS version：4.1+

Limitations

• Persistent Volumes must be used. emptyDirs will possibly result in a loss of data

Project directory

Directory Name	Description
plugin	Help Nacos cluster achieve automatic scaling in K8s
deploy	Deploy the required files

Configuration properties

• nacos-pvc-nfs.yaml or nacos-quick-start.yaml

Name	Required	Description
mysql.master.db.name	Y	Master database name
mysql.master.port	N	Master database port
mysql.slave.port	N	Slave database port
mysql.master.user	Y	Master database username
mysql.master.password	Y	Master database password
NACOS_REPLICAS	Y	The number of clusters must be consistent with the value of the replicas attribute
NACOS_SERVER_PORT	N	Nacos port,default:8848
PREFER_HOST_MODE	Y	Enable Nacos cluster node domain name support

• nfs deployment.yaml

Name	Required	Description
NFS_SERVER	Y	NFS server address
NFS_PATH	Y	NFS server shared directory
server	Y	NFS server address
path	Y	NFS server shared directory

• mysql yaml

Name	Required	Description
MYSQL_ROOT_PASSWORD	N	Root password
MYSQL_DATABASE	Y	Database Name
MYSQL_USER	Y	Database Username
MYSQL_PASSWORD	Y	Database Password
MYSQL_REPLICATION_USER	Y	Master-slave replication username
MYSQL_REPLICATION_PASSWORD	Y	Master-slave replication password
Nfs:server	Y	NFS server address
Nfs:path	Y	NFS server shared path