Deploying redis5.0.14 on Kubernetes (k8s)

Environmental preparation

First you need a Kubernetes environment, please refer to the article I wrote:https://blog.csdn.net/m0_51510236/article/details/130842122

Create namespace

We can choose the following two ways to create a namespace. The name of the namespace I created this time isdeploy-test, which can be changed. This is just a demonstration:

• Command to create directly

kubectl create namespace deploy-test

• yaml creation (recommended)

apiVersion: v1
kind: Namespace
metadata:
  name: deploy-test
spec: {
    
    }
status: {
    
    }

Prepare PV and PVC

I explained what PV and PVC are in my previous article:https://blog.csdn.net/m0_51510236/article/details/132482351 a>

Install nfs

This article is used directly. The preparation this time is nfs for storage, so three servers need to be installed. nfs-utils:

yum install -y nfs-utils

As shown in the figure, all three servers have been installed:

Then we execute these two lines of commands on the main server or nfs server:

mkdir -p /data/nfs/redis
cat >> /etc/exports << EOF
/data/nfs/redis *(rw,sync,no_root_squash)
EOF

This line of command is exposed/data/nfs/redis to the directory accessed by the nfs client, which is used to store redis data and logs. As a result, we need to open the nfs server and execute the following line Command:

systemctl enable --now nfs-server

Check the exposure results after exposure:

showmount -e nfs服务端地址

The test is as shown in the figure:

Okay, next nfs will be installed.

Prepare for PV

Upload yaml directly and modify it according to the prompt content:

apiVersion: v1
kind: PersistentVolume
metadata:
  name: deploy-redis-nfs-pv # PV的名字
  namespace: deploy-test # 命名空间
spec:
  capacity:
    storage: 1Gi # 申请的大小
  accessModes:
    - ReadWriteMany # 访问模式为多节点读写
  nfs:
    server: 192.168.1.160 # nfs服务器地址，注意修改为你自己的
    path: /data/nfs/redis # nfs的远程目录
  storageClassName: "nfs" # 存储类名字为nfs

The creation results show:

Prepare PVC

Go directly to yaml. There is nothing to modify other than changing the name:

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: deploy-redis-nfs-pvc # pvc名字
  namespace: deploy-test # 命名空间
spec:
  accessModes:
    - ReadWriteMany # 多节点读写
  storageClassName: "nfs" # 存储类类型为nfs
  resources:
    requests:
      storage: 1Gi # 申请存储空间的大小
  volumeName: deploy-redis-nfs-pv # 对应上面的pv名字

View the creation of pvc:

View the status of both (kubectl get pv,pvc -o wide -n deploy-test):

Deploy redis

Create a redis configuration file

First, let’s specify the content of the configuration file (be sure to change your password):

# 关闭保护模式
protected-mode no

# redis链接密码
requirepass redis

# 日志级别
loglevel warning

# 日志存放目录
logfile "/data/redis.log"

# 数据文件目录
dir /data
dbfilename dump.rdb

# 数据库数量
databases 16

# 保存数据库到数据文件
save 900 1
save 300 10
save 60 10000

Note uploading this configuration file to the server:

Then we create a configmap for this file:

kubectl create configmap deploy-redis-config -n deploy-test --from-file=redis.conf --dry-run=client -o yaml

The above line of command will generate a yaml file based on redis.conf:

So the yaml file that creates this configmap is:

apiVersion: v1
data:
  redis.conf: |
    # 关闭保护模式
    protected-mode no

    # redis链接密码
    requirepass redis

    # 日志级别
    loglevel warning

    # 日志存放目录
    logfile "/data/redis.log"

    # 数据文件目录
    dir /data
    dbfilename dump.rdb

    # 数据库数量
    databases 16

    # 保存数据库到数据文件
    save 900 1
    save 300 10
    save 60 10000
kind: ConfigMap
metadata:
  name: deploy-redis-config
  namespace: deploy-test

Create a configmap as shown in the figure:

department script

apiVersion: v1
kind: Service
metadata:
  name: deploy-redis-svc
  namespace: deploy-test
  labels:
    app: redis
spec:
  ports:
  - port: 6379
    name: redis
    targetPort: 6379
    nodePort: 30379
  selector:
    app: redis
  type: NodePort
  sessionAffinity: ClientIP

---

apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: deploy-redis
  namespace: deploy-test
spec:
  selector:
    matchLabels:
      app: redis # 必须匹配 .spec.template.metadata.labels
  serviceName: "deploy-redis-svc"
  replicas: 1
  template:
    metadata:
      labels:
        app: redis # 必须匹配 .spec.selector.matchLabels
    spec:
      terminationGracePeriodSeconds: 10
      containers:
      - command:
        - "redis-server"
        - "/usr/local/etc/redis.conf"
        name: redis
        image: redis:5.0.14
        ports:
        - containerPort: 6379
          name: redis
        volumeMounts:
        - name: redis-data
          mountPath: /data
        - name: redis-config
          mountPath: /usr/local/etc
          readOnly: true
      volumes:
      - name: redis-data
        persistentVolumeClaim:
          claimName: deploy-redis-nfs-pvc
      - name: redis-config
        configMap:
          name: deploy-redis-config
          items:
          - key: redis.conf
            path: redis.conf

Next, I will explain the more important scripts inside.

Mount data directory

There is a string of code in StatefulSet.spec.template.spec.volumes:

      - name: redis-data
        persistentVolumeClaim:
          claimName: deploy-redis-nfs-pvc

This string of code is to use deploy-redis-nfs-pvc this pvc for data storage, and give this mount a name redis-data, and then a>StatefulSet.spec.template.spec.containers There is a string of code:

        - name: redis-data
          mountPath: /data

This string of code means to use the data mount named redis-data and mount it in the /data directory of the pod

Mount configuration file

There is a string of code in StatefulSet.spec.template.spec.volumes:

      - name: redis-config
        configMap:
          name: deploy-redis-config
          items:
          - key: redis.conf
            path: redis.conf

This string of code means to read the configmapdeploy-redis-config and name it redis-config, and then get the redis.conf inside Configuration file, named redis.conf, and then there is a string of code in StatefulSet.spec.template.spec.containers:

        - name: redis-config
          mountPath: /usr/local/etc
          readOnly: true

This string of code means to use the configuration file named redis-config and mount it in the /usr/local/etc of the pod in a read-only manner

Start redis through the specified configuration file

There is this line of code in `StatefulSet.spec.template.spec.containers:

      - command:
        - "redis-server"
        - "/usr/local/etc/redis.conf"

This line of code means to use the/usr/local/etc/redis.conf configuration file to start redis. This configuration file is configured in configmap. When we execute the deployed yaml, we can view the results:

Execute the following command to check the deployment progress:

kubectl get all -o wide -n deploy-test

Seeing this means the deployment is complete:

Access within the cluster

The access address of the StatefulSet application is:

<pod名称>.<service名称>.<命名空间名称>.svc.cluster.local

Then the pod access address exposed this time is:

deploy-redis-0.deploy-redis-svc.deploy-test.svc.cluster.local

Try to parse and verify:

External linkRedis

We can try linking directly using IntelliJ IDEA or other linking tools:

Display link is successful (if there is a password, please enter the password):

And the operation is no problem:

We come to the data directory and check that the data in the container has been successfully exposed to the nfs directory:
At this point, the installation of redis on Kubernetes is complete!