k8s部署nacos集群：3个pod、连接外部mysql读写分离集群

阳光穿透心脏的1/2处 2023-10-05 19:12 1阅读 0赞

## 部署mysql ##

*  nacos连接外部mysql sts
 *  使用`mysql-0.mysql.dmgeo-lib.svc.cluster.local`进行连接，同一ns下可以省略后面的。
 *  需要先初始化数据：创建nacos\_config数据库，并source导入如下sql：
    
     *  `https://github.com/alibaba/nacos/edit/master/distribution/conf/nacos-mysql.sql`
 *  将宿主机文件拷贝进pod里面
    
     *  `sudo kubectl cp nacos-mysql.sql mysql-0:/var/lib/mysql/nacos_config -n dmgeo-lib`
 *  然后在mysql-0 pod里面执行source导入操作。

[root@k8s-n0 nacos]# cat ../mysql/sts/mysql-cluster.yaml 
    apiVersion: v1
    kind: ConfigMap
    metadata:
      name: mysql-configmap
      namespace: dmgeo-lib
      labels:
        app: mysql
    data:
      primary.cnf: |
        # Apply this config only on the primary.
        [mysqld]
        log-bin
      replica.cnf: |
        # Apply this config only on replicas.
        [mysqld]
        super-read-only
    
    ---
    # Headless service for stable DNS entries of StatefulSet members.
    apiVersion: v1
    kind: Service
    metadata:
      name: mysql
      namespace: dmgeo-lib
      labels:
        app: mysql
    spec:
      ports:
      - name: mysql
        port: 3306
      clusterIP: None
      selector:
        app: mysql
    ---
    # Client service for connecting to any MySQL instance for reads.
    # For writes, you must instead connect to the primary: mysql-0.mysql.
    apiVersion: v1
    kind: Service
    metadata:
      name: mysql-read
      namespace: dmgeo-lib
      labels:
        app: mysql
    spec:
      ports:
      - name: mysql
        port: 3306
      selector:
        app: mysql
    
    ---
    apiVersion: apps/v1
    kind: StatefulSet
    metadata:
      name: mysql
      namespace: dmgeo-lib
    spec:
      selector:
        matchLabels:
          app: mysql
      serviceName: mysql
      replicas: 3 
      template:
        metadata:
          labels:
            app: mysql
        spec:
          initContainers:
          - name: init-mysql
            image: 192.168.145.28:1603/lego/mysql/mysql:5.7
            command:
            - bash
            - "-c"
            - |
              set -ex
              # Generate mysql server-id from pod ordinal index.
              [[ `hostname` =~ -([0-9]+)$ ]] || exit 1
              ordinal=${BASH_REMATCH[1]}
              echo [mysqld] > /mnt/conf.d/server-id.cnf
              # Add an offset to avoid reserved server-id=0 value.
              echo server-id=$((100 + $ordinal)) >> /mnt/conf.d/server-id.cnf
              # Copy appropriate conf.d files from config-map to emptyDir.
              if [[ $ordinal -eq 0 ]]; then
                cp /mnt/config-map/primary.cnf /mnt/conf.d/
              else
                cp /mnt/config-map/replica.cnf /mnt/conf.d/
              fi
            volumeMounts:
            - name: mysql-conf
              mountPath: /mnt/conf.d
            - name: mysql-configmap
              mountPath: /mnt/config-map
          - name: clone-mysql
            image: 192.168.145.28:1603/lego/mysql/twoeo/gcr.io-google-samples-xtrabackup:latest
            command:
            - bash
            - "-c"
            - |
              set -ex
              # Skip the clone if data already exists.
              [[ -d /var/lib/mysql/mysql ]] && exit 0
              # Skip the clone on primary (ordinal index 0).
              [[ `hostname` =~ -([0-9]+)$ ]] || exit 1
              ordinal=${BASH_REMATCH[1]}
              [[ $ordinal -eq 0 ]] && exit 0
              # Clone data from previous peer.
              ncat --recv-only mysql-$(($ordinal-1)).mysql 3307 | xbstream -x -C /var/lib/mysql
              # Prepare the backup.
              xtrabackup --prepare --target-dir=/var/lib/mysql
            volumeMounts:
            - name: mysql-data
              mountPath: /var/lib/mysql
              subPath: mysql
            - name: mysql-conf
              mountPath: /etc/mysql/conf.d
          containers:
          - name: mysql
            image: 192.168.145.28:1603/lego/mysql/mysql:5.7
            env:
            #- name: MYSQL_ROOT_PASSWORD
            #  value: 123456
            - name: MYSQL_ALLOW_EMPTY_PASSWORD
              value: "1"
            - name: MYSQL_ROOT_PASSWORD
              value: "root"
            - name: MYSQL_DATABASE
              value: "nacos_config"
            - name: MYSQL_USER
              value: "nacos"
            - name: MYSQL_PASSWORD
              value: "nacos"
            ports:
            - name: mysql
              containerPort: 3306
            volumeMounts:
            - name: mysql-data
              mountPath: /var/lib/mysql
              subPath: mysql
            - name: mysql-conf
              mountPath: /etc/mysql/conf.d
            resources:
              requests:
                cpu: 500m
                memory: 1Gi
            livenessProbe:
              exec:
                command: ["mysqladmin", "ping"]
              initialDelaySeconds: 30
              periodSeconds: 10
              timeoutSeconds: 5
            readinessProbe:
              exec:
                # Check we can execute queries over TCP (skip-networking is off).
                command: ["mysql", "-h", "127.0.0.1", "-e", "SELECT 1"]
              initialDelaySeconds: 5
              periodSeconds: 2
              timeoutSeconds: 1
          - name: xtrabackup
            image: 192.168.145.28:1603/lego/mysql/twoeo/gcr.io-google-samples-xtrabackup:latest
            ports:
            - name: xtrabackup
              containerPort: 3307
            command:
            - bash
            - "-c"
            - |
              set -ex
              cd /var/lib/mysql
    
              # Determine binlog position of cloned data, if any.
              if [[ -f xtrabackup_slave_info && "x$(<xtrabackup_slave_info)" != "x" ]]; then
                # XtraBackup already generated a partial "CHANGE MASTER TO" query
                # because we're cloning from an existing replica. (Need to remove the tailing semicolon!)
                cat xtrabackup_slave_info | sed -E 's/;$//g' > change_master_to.sql.in
                # Ignore xtrabackup_binlog_info in this case (it's useless).
                rm -f xtrabackup_slave_info xtrabackup_binlog_info
              elif [[ -f xtrabackup_binlog_info ]]; then
                # We're cloning directly from primary. Parse binlog position.
                [[ `cat xtrabackup_binlog_info` =~ ^(.*?)[[:space:]]+(.*?)$ ]] || exit 1
                rm -f xtrabackup_binlog_info xtrabackup_slave_info
                echo "CHANGE MASTER TO MASTER_LOG_FILE='${
        BASH_REMATCH[1]}',\
                      MASTER_LOG_POS=${
        BASH_REMATCH[2]}" > change_master_to.sql.in
              fi
    
              # Check if we need to complete a clone by starting replication.
              if [[ -f change_master_to.sql.in ]]; then
                echo "Waiting for mysqld to be ready (accepting connections)"
                until mysql -h 127.0.0.1 -e "SELECT 1"; do sleep 1; done
    
                echo "Initializing replication from clone position"
                mysql -h 127.0.0.1 \
                      -e "$(<change_master_to.sql.in), \
                              MASTER_HOST='mysql-0.mysql', \
                              MASTER_USER='root', \
                              MASTER_PASSWORD='', \
                              MASTER_CONNECT_RETRY=10; \
                            START SLAVE;" || exit 1
                # In case of container restart, attempt this at-most-once.
                mv change_master_to.sql.in change_master_to.sql.orig
              fi
    
              # Start a server to send backups when requested by peers.
              exec ncat --listen --keep-open --send-only --max-conns=1 3307 -c \
                "xtrabackup --backup --slave-info --stream=xbstream --host=127.0.0.1 --user=root"
            volumeMounts:
            - name: mysql-data
              mountPath: /var/lib/mysql
              subPath: mysql
            - name: mysql-conf
              mountPath: /etc/mysql/conf.d
            resources:
              requests:
                cpu: 100m
                memory: 100Mi
          volumes:
          - name: mysql-conf
            emptyDir: {
        }
          - name: mysql-configmap
            configMap:
              name: mysql-configmap
      volumeClaimTemplates:
      - metadata:
          name: mysql-data
        spec:
          accessModes: ["ReadWriteOnce"]
          resources:
            requests:
              storage: 10Gi

## 部署nacos ##

all-in-one.yaml

[root@k8s-n0 nacos]# cat all-in-one.yaml 
    apiVersion: v1
    kind: ConfigMap
    metadata:
      name: nacos-cm
      namespace: dmgeo-lib
    data:
      mysql.host: "mysql-0.mysql"
      mysql.db.name: "nacos_config"
      mysql.port: "3306"
      mysql.user: "root"
      mysql.password: ""
    
    ---
    apiVersion: v1
    kind: Service
    metadata:
      name: nacos-svc
      namespace: dmgeo-lib
      labels:
        app: nacos-svc
    spec:
      type: NodePort
      ports:
        - port: 8848
          name: nacos-svc
          targetPort: 8848
          nodePort: 8848
      selector:
        app: nacos
    ---
    apiVersion: v1
    kind: Service
    metadata:
      name: nacos-headless
      namespace: dmgeo-lib
      labels:
        app: nacos-headless
    spec:
      type: ClusterIP
      clusterIP: None
      ports:
        - port: 8848
          name: server
          targetPort: 8848
        - port: 7848
          name: rpc
          targetPort: 7848
      clusterIP: None
      selector:
        app: nacos
    ---
    apiVersion: apps/v1
    kind: StatefulSet
    metadata:
      name: nacos
      namespace: dmgeo-lib
    spec:
      serviceName: nacos-headless
      replicas: 3
      template:
        metadata:
          labels:
            app: nacos
          annotations:
            pod.alpha.kubernetes.io/initialized: "true"
        spec:
          imagePullSecrets:           # dokcer仓库密码，不需要的可以去掉
            - name: registry-harbor
          terminationGracePeriodSeconds: 65
          affinity:
            podAntiAffinity:
              requiredDuringSchedulingIgnoredDuringExecution:
                - labelSelector:
                    matchExpressions:
                      - key: "app"
                        operator: In
                        values:
                          - nacos
                  topologyKey: "kubernetes.io/hostname"
          containers:
            - name: k8snacos
              imagePullPolicy: Always
              image: 192.168.145.28:1603/lego/nacos/nacos-server:latest
              resources:
                requests:
                  memory: "2Gi"
                  cpu: "500m"
              ports:
                - containerPort: 8848
                  name: client
                - containerPort: 7848
                  name: rpc
              env:
                - name: NACOS_REPLICAS
                  value: "3"
                - name: MYSQL_SERVICE_HOST
                  valueFrom:
                    configMapKeyRef:
                      name: nacos-cm
                      key: mysql.host
                - name: MYSQL_SERVICE_DB_NAME
                  valueFrom:
                    configMapKeyRef:
                      name: nacos-cm
                      key: mysql.db.name
                - name: MYSQL_SERVICE_PORT
                  valueFrom:
                    configMapKeyRef:
                      name: nacos-cm
                      key: mysql.port
                - name: MYSQL_SERVICE_USER
                  valueFrom:
                    configMapKeyRef:
                      name: nacos-cm
                      key: mysql.user
                - name: MYSQL_SERVICE_PASSWORD
                  valueFrom:
                    configMapKeyRef:
                      name: nacos-cm
                      key: mysql.password
                - name: MODE
                  value: "cluster"
                - name: NACOS_SERVER_PORT
                  value: "8848"
                - name: PREFER_HOST_MODE
                  value: "hostname"
                - name: NACOS_SERVERS
                  value: "nacos-0.nacos-headless.dmgeo-lib.svc.cluster.local:8848 nacos-1.nacos-headless.dmgeo-lib.svc.cluster.local:8848 nacos-2.nacos-headless.dmgeo-lib.svc.cluster.local:8848"
      selector:
        matchLabels:
          app: nacos