k8s部署redis cluster集群

男娘i 2023-02-19 01:25 125阅读 0赞

k8s以StatefulSet方式部署redis cluster集群：

1. 部署nfs
    
    2. 创建pv
    
    3. 部署redis
    
    4. 初始化redis集群

--------------------

*  主机说明：

<table> 
 <thead> 
  <tr> 
   <th>系统</th> 
   <th>ip</th> 
   <th>角色</th> 
   <th>cpu</th> 
   <th>内存</th> 
   <th>hostname</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td>CentOS 7.8</td> 
   <td>192.168.30.128</td> 
   <td>master</td> 
   <td>&gt;=2</td> 
   <td>&gt;=2G</td> 
   <td>master1</td> 
  </tr> 
  <tr> 
   <td>CentOS 7.8</td> 
   <td>192.168.30.129</td> 
   <td>master</td> 
   <td>&gt;=2</td> 
   <td>&gt;=2G</td> 
   <td>master2</td> 
  </tr> 
  <tr> 
   <td>CentOS 7.8</td> 
   <td>192.168.30.130</td> 
   <td>node</td> 
   <td>&gt;=2</td> 
   <td>&gt;=2G</td> 
   <td>node1</td> 
  </tr> 
  <tr> 
   <td>CentOS 7.8</td> 
   <td>192.168.30.131</td> 
   <td>node</td> 
   <td>&gt;=2</td> 
   <td>&gt;=2G</td> 
   <td>node2</td> 
  </tr> 
  <tr> 
   <td>CentOS 7.8</td> 
   <td>192.168.30.132</td> 
   <td>node</td> 
   <td>&gt;=2</td> 
   <td>&gt;=2G</td> 
   <td>node3</td> 
  </tr> 
 </tbody> 
</table>

kubectl get node
    
    NAME      STATUS   ROLES    AGE   VERSION
    master1   Ready    master   33d   v1.14.0
    master2   Ready    master   33d   v1.14.0
    node1     Ready    <none>   33d   v1.14.0
    node2     Ready    <none>   33d   v1.14.0
    node3     Ready    <none>   33d   v1.14.0

--------------------

### 部署nfs ###

在master2节点上做nfs共享，

yum -y install nfs-utils rpcbind
    
    mkdir -p /data/redis/{ cluster0,cluster1,cluster2,cluster3,cluster4,cluster5}
    
    vim /etc/exports

/data/redis/cluster0 192.168.30.0/24(rw,sync,no_root_squash)
    /data/redis/cluster1 192.168.30.0/24(rw,sync,no_root_squash)
    /data/redis/cluster2 192.168.30.0/24(rw,sync,no_root_squash)
    /data/redis/cluster3 192.168.30.0/24(rw,sync,no_root_squash)
    /data/redis/cluster4 192.168.30.0/24(rw,sync,no_root_squash)
    /data/redis/cluster5 192.168.30.0/24(rw,sync,no_root_squash)

chmod -R 755 /data/redis
    
    exportfs -arv
    
    systemctl enable rpcbind && systemctl start rpcbind
    
    systemctl enable nfs && systemctl start nfs

nfs部署完毕。对于需要使用nfs的node节点，都要安装nfs：

yum -y install nfs-utils

--------------------

### 创建pv ###

*  创建pv：

mkdir -p /home/k8s/redis  && cd /home/k8s/redis
    
    vim pv.yaml

apiVersion: v1
    kind: PersistentVolume
    metadata:
      name: nfs-pv0
    spec:
      capacity:
        storage: 1Gi
      accessModes:
        - ReadWriteMany
      nfs:
        server: 192.168.30.129
        path: /data/redis/cluster0
    
    ---
    apiVersion: v1
    kind: PersistentVolume
    metadata:
      name: nfs-pv1
    spec:
      capacity:
        storage: 1Gi
      accessModes:
        - ReadWriteMany
      nfs:
        server: 192.168.30.129
        path: /data/redis/cluster1
    
    ---
    apiVersion: v1
    kind: PersistentVolume
    metadata:
      name: nfs-pv2
    spec:
      capacity:
        storage: 1Gi
      accessModes:
        - ReadWriteMany
      nfs:
        server: 192.168.30.129
        path: /data/redis/cluster2
    
    ---
    apiVersion: v1
    kind: PersistentVolume
    metadata:
      name: nfs-pv3
    spec:
      capacity:
        storage: 1Gi
      accessModes:
        - ReadWriteMany
      nfs:
        server: 192.168.30.129
        path: /data/redis/cluster3
    
    ---
    apiVersion: v1
    kind: PersistentVolume
    metadata:
      name: nfs-pv4
    spec:
      capacity:
        storage: 1Gi
      accessModes:
        - ReadWriteMany
      nfs:
        server: 192.168.30.129
        path: /data/redis/cluster4
    
    ---
    apiVersion: v1
    kind: PersistentVolume
    metadata:
      name: nfs-pv5
    spec:
      capacity:
        storage: 1Gi
      accessModes:
        - ReadWriteMany
      nfs:
        server: 192.168.30.129
        path: /data/redis/cluster5

kubectl apply -f pv.yaml
    
    kubectl get pv
    
    NAME      CAPACITY   ACCESS MODES   RECLAIM POLICY   STATUS      CLAIM   STORAGECLASS   REASON   AGE
    nfs-pv0   1Gi        RWX            Retain           Available                                   3s
    nfs-pv1   1Gi        RWX            Retain           Available                                   3s
    nfs-pv2   1Gi        RWX            Retain           Available                                   3s
    nfs-pv3   1Gi        RWX            Retain           Available                                   3s
    nfs-pv4   1Gi        RWX            Retain           Available                                   3s
    nfs-pv5   1Gi        RWX            Retain           Available                                   3s

pv创建完毕。

--------------------

### 部署redis ###

vim namespace.yaml

apiVersion: v1
    kind: Namespace
    metadata:
      name: public-service

vim redis.conf

appendonly yes
    cluster-enabled yes
    cluster-config-file /var/lib/redis/nodes.conf
    cluster-node-timeout 5000
    dir /var/lib/redis
    port 6379

vim redis.yaml

apiVersion: v1
    kind: Service
    metadata:
      name: redis
      namespace: public-service
      labels:
        app: redis
    spec:
      selector:
        app: redis
        appCluster: redis-cluster
      ports:
      - name: redis
        port: 6379
      clusterIP: None
      
    ---
    apiVersion: v1
    kind: Service
    metadata:
      name: redis-access
      namespace: public-service
      labels:
        app: redis
    spec:
      selector:
        app: redis
        appCluster: redis-cluster
      ports:
      - name: redis-access
        protocol: TCP
        port: 6379
        targetPort: 6379
    
    ---
    apiVersion: apps/v1
    kind: StatefulSet
    metadata:
      name: redis
      namespace: public-service
    spec:
      serviceName: redis
      replicas: 6
      selector:
        matchLabels:
          app: redis
          appCluster: redis-cluster
      template:
        metadata:
          labels:
            app: redis
            appCluster: redis-cluster
        spec:
          terminationGracePeriodSeconds: 20
          affinity:
            podAntiAffinity:
              preferredDuringSchedulingIgnoredDuringExecution:
              - weight: 100
                podAffinityTerm:
                  labelSelector:
                    matchExpressions:
                    - key: app
                      operator: In
                      values:
                      - redis
                  topologyKey: kubernetes.io/hostname
          containers:
          - name: redis
            image: redis:latest
            command:
              - "redis-server"
            args:
              - "/etc/redis/redis.conf"
              - "--protected-mode"
              - "no"
            resources:
              requests:
                cpu: "500m"
                memory: "500Mi"
            ports:
            - containerPort: 6379
              name: redis
              protocol: TCP
            - containerPort: 16379
              name: cluster
              protocol: TCP
            volumeMounts:
            - name: conf
              mountPath: /etc/redis
            - name: data
              mountPath: /var/lib/redis
          volumes:
          - name: conf
            configMap:
              name: redis-conf
              items:
              - key: redis.conf
                path: redis.conf
      volumeClaimTemplates:
      - metadata:
          name: data
          namespace: public-service
        spec:
          accessModes: [ "ReadWriteMany" ]
          resources:
            requests:
              storage: 1Gi

kubectl apply -f namespace.yaml
    
    kubectl create configmap redis-conf --from-file=redis.conf -n public-service
    
    kubectl apply -f redis.yaml
    
    kubectl get svc -n public-service
    
    NAME           TYPE        CLUSTER-IP    EXTERNAL-IP   PORT(S)    AGE
    redis          ClusterIP   None          <none>        6379/TCP   20s
    redis-access   ClusterIP   10.96.2.100   <none>        6379/TCP   20s
    
    kubectl get pod -n public-service
    
    NAME      READY   STATUS    RESTARTS   AGE
    redis-0   1/1     Running   0          2m43s
    redis-1   1/1     Running   0          2m18s
    redis-2   1/1     Running   0          108s
    redis-3   1/1     Running   0          80s
    redis-4   1/1     Running   0          48s
    redis-5   1/1     Running   0          30s
    
    kubectl get pvc -n public-service
    
    NAME           STATUS   VOLUME    CAPACITY   ACCESS MODES   STORAGECLASS   AGE
    data-redis-0   Bound    nfs-pv4   1Gi        RWX                           3m4s
    data-redis-1   Bound    nfs-pv0   1Gi        RWX                           2m39s
    data-redis-2   Bound    nfs-pv1   1Gi        RWX                           2m9s
    data-redis-3   Bound    nfs-pv2   1Gi        RWX                           101s
    data-redis-4   Bound    nfs-pv3   1Gi        RWX                           69s
    data-redis-5   Bound    nfs-pv5   1Gi        RWX                           51s

`redis-access`这个service方便集群内访问redis集群，redis部署完毕。

--------------------

### 初始化redis集群 ###

使用Redis-tribe工具进行集群的初始化。

*  下载redis-tribe：

kubectl run -it ubuntu --image=ubuntu --restart=Never -n public-service bash
    
    root@ubuntu:/# cat > /etc/apt/sources.list << EOF
    deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial main restricted
    deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial-updates main restricted
    deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial universe
    deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial-updates universe
    deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial multiverse
    deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial-updates multiverse
    deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial-backports main restricted universe multiverse
    deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial-security main restricted
    deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial-security universe
    deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial-security multiverse
    EOF

root@ubuntu:/# apt-get update
    
    root@ubuntu:/# apt-get install -y libncursesw5 libreadline6 libtinfo5 --allow-remove-essential
    
    root@ubuntu:/# apt-get install -y libpython2.7-stdlib python2.7 python-pip redis-tools dnsutils
    
    root@ubuntu:/# pip install --upgrade pip
    
    root@ubuntu:/# pip install redis-trib==0.5.1

*  初始化集群：

root@ubuntu:/# redis-trib.py create \
      `dig +short redis-0.redis.public-service.svc.cluster.local`:6379 \
      `dig +short redis-1.redis.public-service.svc.cluster.local`:6379 \
      `dig +short redis-2.redis.public-service.svc.cluster.local`:6379
      
    root@ubuntu:/# redis-trib.py replicate \
      --master-addr `dig +short redis-0.redis.public-service.svc.cluster.local`:6379 \
      --slave-addr `dig +short redis-3.redis.public-service.svc.cluster.local`:6379
    
    root@ubuntu:/# redis-trib.py replicate \
      --master-addr `dig +short redis-1.redis.public-service.svc.cluster.local`:6379 \
      --slave-addr `dig +short redis-4.redis.public-service.svc.cluster.local`:6379
    
    root@ubuntu:/# redis-trib.py replicate \
      --master-addr `dig +short redis-2.redis.public-service.svc.cluster.local`:6379 \
      --slave-addr `dig +short redis-5.redis.public-service.svc.cluster.local`:6379
      
    root@ubuntu:/# exit

*  查看集群：

kubectl exec -it -n public-service redis-0 bash
    
    root@redis-0:/data# redis-cli -c
    
    127.0.0.1:6379> CLUSTER NODES               #列出节点信息
    
    aac2b3d320da67eedf3512ed0e38a1cdce5bc8fe 172.10.2.55:6379@16379 slave 7c4d60cf32685484ea6c5cb4493a937dfbf6b8a5 0 1592276224727 3 connected
    2efad514b2f3c7fe4530dd6dc63c0df8ffdb793d 172.10.2.54:6379@16379 master - 0 1592276224224 1 connected 0-5461
    524f03526a4b683d7d4de19296431810bfdc22cf 172.10.3.60:6379@16379 slave df5bc3c2e2851d63cdb9f762efde6e1b0d38efed 0 1592276223117 5 connected
    7c4d60cf32685484ea6c5cb4493a937dfbf6b8a5 172.10.4.77:6379@16379 myself,master - 0 1592276224000 2 connected 5462-10922
    df5bc3c2e2851d63cdb9f762efde6e1b0d38efed 172.10.3.59:6379@16379 master - 0 1592276223217 0 connected 10923-16383
    c1dbaaef4a583e372c43eed52c22cd9ad7184d18 172.10.4.78:6379@16379 slave 2efad514b2f3c7fe4530dd6dc63c0df8ffdb793d 0 1592276223719 4 connected
    
    127.0.0.1:6379> CLUSTER INFO                #集群状态
    
    cluster_state:ok
    cluster_slots_assigned:16384
    cluster_slots_ok:16384
    cluster_slots_pfail:0
    cluster_slots_fail:0
    cluster_known_nodes:6
    cluster_size:3
    cluster_current_epoch:5
    cluster_my_epoch:2
    cluster_stats_messages_ping_sent:514
    cluster_stats_messages_pong_sent:491
    cluster_stats_messages_meet_sent:2
    cluster_stats_messages_sent:1007
    cluster_stats_messages_ping_received:491
    cluster_stats_messages_pong_received:516
    cluster_stats_messages_received:1007

redis集群初始化完成，已经形成3主3从的cluster集群。

*  写入数据：

127.0.0.1:6379> SET key1 aaa
    OK
    
    127.0.0.1:6379> SET key2 bbb
    -> Redirected to slot [4998] located at 172.10.2.54:6379
    OK
    
    172.10.2.54:6379> SET key3 ccc
    OK

kubectl exec -it -n public-service redis-4 bash
    
    root@redis-4:/data# redis-cli -c
    
    127.0.0.1:6379> GET key1
    -> Redirected to slot [9189] located at 172.10.4.77:6379
    "aaa"
    
    172.10.4.77:6379> GET key2
    -> Redirected to slot [4998] located at 172.10.2.54:6379
    "bbb"
    
    172.10.2.54:6379> GET key3
    "ccc"

可以看出redis cluster集群是去中心化的，每个节点都是平等的，连接哪个节点都可以获取和设置数据。

*  主从切换：

选择`redis-2`模拟宕掉，测试主从切换，

kubectl get pod -n public-service -o wide
    
    NAME      READY   STATUS      RESTARTS   AGE   IP            NODE    NOMINATED NODE   READINESS GATES
    redis-0   1/1     Running     0          62m   172.10.4.77   node1   <none>           <none>
    redis-1   1/1     Running     0          62m   172.10.2.54   node2   <none>           <none>
    redis-2   1/1     Running     0          61m   172.10.3.59   node3   <none>           <none>
    redis-3   1/1     Running     0          61m   172.10.2.55   node2   <none>           <none>
    redis-4   1/1     Running     0          61m   172.10.4.78   node1   <none>           <none>
    redis-5   1/1     Running     0          61m   172.10.3.60   node3   <none>           <none>
    ubuntu    0/1     Completed   0          57m   172.10.2.56   node2   <none>           <none>
    
    kubectl exec -it -n public-service redis-2 bash
    
    root@redis-2:/data# redis-cli -c
    
    127.0.0.1:6379> ROLE
    
    1) "master"
    2) (integer) 2898
    3) 1) 1) "172.10.3.60"
          2) "6379"
          3) "2898"

可以看到，`redis-2`是master，它的slave是`172.10.3.60`，即`redis-5`。

kubectl delete pod -n public-service redis-2                #模拟节点宕掉
    
    kubectl get pod -n public-service redis-2 -o wide
    
    NAME      READY   STATUS    RESTARTS   AGE   IP            NODE    NOMINATED NODE   READINESS GATES
    redis-2   1/1     Running   0          38s   172.10.3.61   node3   <none>           <none>
    
    kubectl exec -it -n public-service redis-2 bash
    
    root@redis-2:/data# redis-cli -c
    
    127.0.0.1:6379> ROLE
    
    1) "slave"
    2) "172.10.3.60"
    3) (integer) 6379
    4) "connected"
    5) (integer) 3430

kubectl exec -it -n public-service redis-5 bash
    
    root@redis-5:/data# redis-cli -c
    
    127.0.0.1:6379> ROLE
    
    1) "master"
    2) (integer) 3584
    3) 1) 1) "172.10.3.61"
          2) "6379"
          3) "3570"
          
    127.0.0.1:6379> CLUSTER NODES
    
    aac2b3d320da67eedf3512ed0e38a1cdce5bc8fe 172.10.2.55:6379@16379 slave 7c4d60cf32685484ea6c5cb4493a937dfbf6b8a5 0 1592278859530 2 connected
    2efad514b2f3c7fe4530dd6dc63c0df8ffdb793d 172.10.2.54:6379@16379 master - 0 1592278859000 1 connected 0-5461
    c1dbaaef4a583e372c43eed52c22cd9ad7184d18 172.10.4.78:6379@16379 slave 2efad514b2f3c7fe4530dd6dc63c0df8ffdb793d 0 1592278859000 1 connected
    524f03526a4b683d7d4de19296431810bfdc22cf 172.10.3.60:6379@16379 myself,master - 0 1592278857000 6 connected 10923-16383
    7c4d60cf32685484ea6c5cb4493a937dfbf6b8a5 172.10.4.77:6379@16379 master - 0 1592278858021 2 connected 5462-10922
    df5bc3c2e2851d63cdb9f762efde6e1b0d38efed 172.10.3.61:6379@16379 slave 524f03526a4b683d7d4de19296431810bfdc22cf 0 1592278859000 6 connected

可以看到，`redis-2`在重启之后变为slave，而它之前的slave——`redis-5`变为master，而且是新`redis-2`的master。

集群的主从切换没有问题。k8s部署redis cluster集群完成。

--------------------