zookeeper集群搭建
zookeeper下载地址：https://zookeeper.apache.org/releases.html
制作zookeeper镜像
将压缩包上传到服务器上并解压：
链接：https://pan.baidu.com/s/1z9j57t1joScozOjxnqzB3w
提取码：hkc9
下载slim_java:8镜像，并上传到harbor（zookeeper需要jdk环境）
nerdctl pull elevy/slim_java:8 nerdctl tag elevy/slim_java:8 harbor.wyh.net/test-sy/slim_java:8 nerdctl push harbor.wyh.net/test-sy/slim_java:8
修改dockerfile，将源镜像地址配置成：harbor.wyh.net/test-sy/slim_java:8
修改build-command.sh文件（镜像制作脚本），将镜像上传到harbor上：
cat <<EOF >build-command.sh #!/bin/bash TAG=$1 #docker build -t harbor.magedu.net/magedu/zookeeper:${TAG} . #sleep 1 #docker push harbor.magedu.net/magedu/zookeeper:${TAG} nerdctl build -t harbor.wyh.net/test-sy/zookeeper:${TAG} . nerdctl push harbor.wyh.net/test-sy/zookeeper:${TAG} EOF chmod +x build-command.sh bash build-command.sh v20220817
运行服务
在存储服务（nfs共享目录）中创建zookeeper使目录
mkdir /data/kubernetes/wyh/{zookeeper-datadir-1,zookeeper-datadir-2,zookeeper-datadir-3} -p
创建pv
cat <<EOF >zookeeper-pv.yaml apiVersion: v1 kind: PersistentVolume metadata: name: zookeeper-datadir-pv-1 spec: capacity: storage: 5Gi accessModes: - ReadWriteOnce nfs: server: 192.168.213.21 path: /data/kubernetes/wyh/zookeeper-datadir-1 --- apiVersion: v1 kind: PersistentVolume metadata: name: zookeeper-datadir-pv-2 spec: capacity: storage: 5Gi accessModes: - ReadWriteOnce nfs: server: 192.168.213.21 path: /data/kubernetes/wyh/zookeeper-datadir-2 --- apiVersion: v1 kind: PersistentVolume metadata: name: zookeeper-datadir-pv-3 spec: capacity: storage: 5Gi accessModes: - ReadWriteOnce nfs: server: 192.168.213.21 path: /data/kubernetes/wyh/zookeeper-datadir-3 EOF kubectl apply -f zookeeper-pv.yaml
创建pvc关联pv
cat <<EOF >zookeeper-pvc.yaml apiVersion: v1 kind: PersistentVolumeClaim metadata: name: zookeeper-datadir-pvc-1 namespace: wyh-ns spec: accessModes: - ReadWriteOnce volumeName: zookeeper-datadir-pv-1 resources: requests: storage: 5Gi --- apiVersion: v1 kind: PersistentVolumeClaim metadata: name: zookeeper-datadir-pvc-2 namespace: wyh-ns spec: accessModes: - ReadWriteOnce volumeName: zookeeper-datadir-pv-2 resources: requests: storage: 5Gi --- apiVersion: v1 kind: PersistentVolumeClaim metadata: name: zookeeper-datadir-pvc-3 namespace: wyh-ns spec: accessModes: - ReadWriteOnce volumeName: zookeeper-datadir-pv-3 resources: requests: storage: 5Gi EOF kubectl apply -f zookeeper-pvc.yaml
创建zookeeper的deploy文件
cat <<EOF >zookeeper-deploy.yaml apiVersion: v1 kind: Service metadata: name: zookeeper namespace: wyh-ns spec: ports: - name: client port: 2181 selector: app: zookeeper --- apiVersion: v1 kind: Service metadata: name: zookeeper1 namespace: wyh-ns spec: type: NodePort ports: - name: client port: 2181 nodePort: 32181 - name: followers port: 2888 - name: election port: 3888 selector: app: zookeeper server-id: "1" --- apiVersion: v1 kind: Service metadata: name: zookeeper2 namespace: wyh-ns spec: type: NodePort ports: - name: client port: 2181 nodePort: 32182 - name: followers port: 2888 - name: election port: 3888 selector: app: zookeeper server-id: "2" --- apiVersion: v1 kind: Service metadata: name: zookeeper3 namespace: wyh-ns spec: type: NodePort ports: - name: client port: 2181 nodePort: 32183 - name: followers port: 2888 - name: election port: 3888 selector: app: zookeeper server-id: "3" --- kind: Deployment #apiVersion: extensions/v1beta1 apiVersion: apps/v1 metadata: name: zookeeper1 namespace: wyh-ns spec: replicas: 1 selector: matchLabels: app: zookeeper template: metadata: labels: app: zookeeper server-id: "1" spec: volumes: - name: data emptyDir: {} - name: wal emptyDir: medium: Memory containers: - name: server image: harbor.wyh.net/test-sy/zookeeper:v20220817 imagePullPolicy: IfNotPresent env: - name: MYID value: "1" - name: SERVERS value: "zookeeper1,zookeeper2,zookeeper3" - name: JVMFLAGS value: "-Xmx2G" ports: - containerPort: 2181 - containerPort: 2888 - containerPort: 3888 volumeMounts: - mountPath: "/zookeeper/data" name: zookeeper-datadir-pvc-1 volumes: - name: zookeeper-datadir-pvc-1 persistentVolumeClaim: claimName: zookeeper-datadir-pvc-1 --- kind: Deployment #apiVersion: extensions/v1beta1 apiVersion: apps/v1 metadata: name: zookeeper2 namespace: wyh-ns spec: replicas: 1 selector: matchLabels: app: zookeeper template: metadata: labels: app: zookeeper server-id: "2" spec: volumes: - name: data emptyDir: {} - name: wal emptyDir: medium: Memory containers: - name: server image: harbor.wyh.net/test-sy/zookeeper:v20220817 imagePullPolicy: IfNotPresent env: - name: MYID value: "2" - name: SERVERS value: "zookeeper1,zookeeper2,zookeeper3" - name: JVMFLAGS value: "-Xmx2G" ports: - containerPort: 2181 - containerPort: 2888 - containerPort: 3888 volumeMounts: - mountPath: "/zookeeper/data" name: zookeeper-datadir-pvc-2 volumes: - name: zookeeper-datadir-pvc-2 persistentVolumeClaim: claimName: zookeeper-datadir-pvc-2 --- kind: Deployment #apiVersion: extensions/v1beta1 apiVersion: apps/v1 metadata: name: zookeeper3 namespace: wyh-ns spec: replicas: 1 selector: matchLabels: app: zookeeper template: metadata: labels: app: zookeeper server-id: "3" spec: volumes: - name: data emptyDir: {} - name: wal emptyDir: medium: Memory containers: - name: server image: harbor.wyh.net/test-sy/zookeeper:v20220817 imagePullPolicy: IfNotPresent env: - name: MYID value: "3" - name: SERVERS value: "zookeeper1,zookeeper2,zookeeper3" - name: JVMFLAGS value: "-Xmx2G" ports: - containerPort: 2181 - containerPort: 2888 - containerPort: 3888 volumeMounts: - mountPath: "/zookeeper/data" name: zookeeper-datadir-pvc-3 volumes: - name: zookeeper-datadir-pvc-3 persistentVolumeClaim: claimName: zookeeper-datadir-pvc-3 EOF kubectl apply -f zookeeper-deploy.yaml kubectl get pod -nwyh-ns | grep zookeeper
！！！验证集群！！！
kubectl exec -it zookeeper3-568d69f5dc-9dw4n -nwyh-ns -- /zookeeper/bin/zkServer.sh status
有follower节点，证明是集群
测试leader节点出现问题后是否会重新选举（因为现在2节点是leader，现在将2节点搞坏）：
将拉取的镜像改成一个不存在的镜像
kubectl apply -f zookeeper-deploy.yaml kubectl get pod -nwyh-ns | grep zookeeper
检查哪个节点是leader
事实证明，3已经是leader，集群搭建成功！！！
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zookeeper集群：半数机制，需要集群中需要有半数以上的节点存活，所以需要奇数节点（至少三台）
集群节点id：myid，每个节点的编号，在集群中唯一表示
事务id：zxid，zookeeper会给给一个请求分配事务id，由leader同一分配，全局唯一，不断递增
集群服务器角色：
-
leader：主节点
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follower：从节点
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observer：观察者
集群节点状态：
-
LOOKING：寻找leader状态，此时正在选举
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FOLLOWING：表示当前节点是follower
-
LEADING：当前节点是主节点
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OBSERVING：观察者状态（不参加竞选投票）
选举场景：
-
Zookeeper集群初始化时选举
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leader节点异常失联时选举
选举前提条件
-
集群节点要保证一半以上的节点运行，如果集群节点有3台，那要保证2台以上（包括2台）正常使用，如果有5台，那要保证3台以上（包括3台）正常使用
-
节点处于LOOKING状态，说明此时集群没有leader
初始化选举：例，集群有a(myid=2)，b(myid=2)，c(myid=3)，d(myid=4)，e(myid=5)五个个节点
-
a向自己投一票，此时a票数为1，票数为过半，所以a处于LOOKING状态
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b向自己投一票，然后和a交换选票信息，a发现b的myid大于自己，所以a将票投给b，a为0票，b为2票，为过半，a和b状态都为LOOKING
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c发起一次选举，同理a和b会将选票信息给c，c的票数为三，大于一半，所以c改为LEADING，a和b状态改为FOLLOWING
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d发起一次选举，因为a和b已经不是LOCKING，所以他只有自己一票，少数服从多数，d也将选票给c，d为FOLLOWING
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e同理d
集群重新选举：
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首先比较zxid，zxid大的为LEADING
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zxid一样那就比较myid
