kubernets应用

知识库容器技术kubernetes实战kubernetes大约 3 分钟

使用 Ceph 做持久化存储创建 MySQL 集群

https://jimmysong.io/kubernetes-handbook/practice/using-ceph-for-persistent-storage.htmlopen in new window

配置 Ceph

kubernetes 提供了一种更加方便的动态创建 PV 的方式；也就是说使用 StoragaClass 时无需预先创建固定大小的 PV，等待使用者创建 PVC 来使用；而是直接创建 PVC 即可分配使用。

安装 ceph 客户端

yum install -y ceph-common

生成 Ceph secret

grep key /opt/ceph/etc/ceph.client.admin.keyring |awk '{printf "%s", $NF}'|base64

创建租户

cat << EOF >> bedrock-namespace.yaml
apiVersion: v1
kind: Namespace
metadata:
  name: bedrock
EOF
kubectl create -f bedrock-namespace.yml

创建 Ceph secret

cat << EOF >> ceph-secret.yaml
apiVersion: v1
kind: Secret
metadata:
  name: ceph-secret
  namespace: bedrock
type: "kubernetes.io/rbd"
data:
  key: QVFDbmdWWmo3V0FxT3hBQVpyb0hidDdTc05seVBIOUhzNG1LT1E9PQ==
EOF
kubectl create -f ceph-secret.yaml

创建 StorageClass

cat << EOF >> ceph-class.yaml
apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
   name: ceph-web
provisioner: kubernetes.io/rbd
parameters:
  monitors: 192.168.10.81:6789
  adminId: admin
  adminSecretName: ceph-secret
  adminSecretNamespace: bedrock
  pool: rbd     # 此处默认是rbd池，生产上建议自己创建存储池隔离 rbd | kube
  userId: admin
  userSecretName: ceph-secret
EOF
kubectl create -f ceph-class.yaml

配置 MySQL

1. 创建 MySQL 配置文件

创建 mysql-config.yaml 文件内容为：

apiVersion: v1
kind: ConfigMap
metadata:
  name: mysql-config-vol
  namespace: galera
  labels:
    app: mysql
data:
  mariadb.cnf: |
    [client]
    default-character-set = utf8
    [mysqld]
    character-set-server  = utf8
    collation-server      = utf8_general_ci
    # InnoDB optimizations
    innodb_log_file_size  = 64M
  galera.cnf: |
    [galera]
    user = mysql
    bind-address = 0.0.0.0
    # Optimizations
    innodb_flush_log_at_trx_commit = 0
    sync_binlog = 0
    expire_logs_days = 7
    # Required settings
    default_storage_engine = InnoDB
    binlog_format = ROW
    innodb_autoinc_lock_mode = 2
    query_cache_size = 0
    query_cache_type = 0
    # MariaDB Galera settings
    #wsrep_debug=ON
    wsrep_on=ON
    wsrep_provider=/usr/lib/galera/libgalera_smm.so
    wsrep_sst_method=rsync
    # Cluster settings (automatically updated)
    wsrep_cluster_address=gcomm://
    wsrep_cluster_name=galera
    wsrep_node_address=127.0.0.1

2. 创建 MySQL root 用户和密码

## 创建加密密码
echo -n 123456|base64
## MTIzNDU2
## 注意：一定要用-n 去掉换行符，不然会报错。

创建 MySQL secret

创建 mysql-secret.yaml 文件内容为：

apiVersion: v1
kind: Secret
metadata:
  name: mysql-secrets
  namespace: galera
  labels:
    app: mysql
data:
  # Root password: changeit run  echo -n 123456|base64
  root-password: MTIzNDU2
  # Root user: changeit run  echo -n root|base64
  root-user: cm9vdA==

3. 创建 yaml 配置文件

创建 MySQL 的 yaml 文件 galera-mariadb.yaml 内容为：

apiVersion: v1
kind: Service
metadata:
  annotations:
    service.alpha.kubernetes.io/tolerate-unready-endpoints: "true"
  name: mysql
  namespace: galera
  labels:
    app: mysql
    tier: data
spec:
  ports:
  - port: 3306
    name: mysql
  clusterIP: None
  selector:
    app: mysql
---
apiVersion: apps/v1beta1
kind: StatefulSet
metadata:
  name: mysql
  namespace: galera
spec:
  serviceName: "mysql"
  replicas: 3
  template:
    metadata:
      labels:
        app: mysql
        tier: data
      annotations:
        pod.beta.kubernetes.io/init-containers: '[
          {
            "name": "galera-init",
            "image": "harbor-001.jimmysong.io/library/k8s-galera-init:latest",
            "args": ["-service=mysql"],
            "env": [
              {
                "name": "POD_NAMESPACE",
                "valueFrom": {
                  "fieldRef": { "apiVersion": "v1", "fieldPath": "metadata.namespace" }
                }
              },
              {
                "name": "SAFE_TO_BOOTSTRAP",
                "value": "1"
              },
              {
                "name": "DEBUG",
                "value": "1"
              }
            ],
            "volumeMounts": [
              {
                "name": "config",
                "mountPath": "/etc/mysql/conf.d"
              },
              {
                "name": "data",
                "mountPath": "/var/lib/mysql"
              }
            ]
          }
        ]'
    spec:
      terminationGracePeriodSeconds: 10
      containers:
      - name: mysql
        image: harbor-001.jimmysong.io/library/mariadb:10.1
        imagePullPolicy: IfNotPresent
        ports:
        - containerPort: 3306
          name: mysql
        - containerPort: 4444
          name: sst
        - containerPort: 4567
          name: replication
        - containerPort: 4568
          name: ist
        env:
        - name: MYSQL_ROOT_PASSWORD
          valueFrom:
            secretKeyRef:
              name: mysql-secrets
              key: root-password
        - name: MYSQL_ROOT_USER
          valueFrom:
            secretKeyRef:
              name: mysql-secrets
              key: root-user
        - name: MYSQL_INITDB_SKIP_TZINFO
          value: "yes"
        livenessProbe:
          exec:
            command: ["sh", "-c", "mysql -u\"${MYSQL_ROOT_USER:-root}\" -p\"${MYSQL_ROOT_PASSWORD}\" -e 'show databases;'"]
          initialDelaySeconds: 60
          timeoutSeconds: 5
        readinessProbe:
          exec:
            command: ["sh", "-c", "mysql -u\"${MYSQL_ROOT_USER:-root}\" -p\"${MYSQL_ROOT_PASSWORD}\" -e 'show databases;'"]
          initialDelaySeconds: 20
          timeoutSeconds: 5
        volumeMounts:
        - name: config
          mountPath: /etc/mysql/conf.d
        - name: data
          mountPath: /var/lib/mysql
      volumes:
      - name: config
        configMap:
          name: mysql-config-vol
      imagePullSecrets:
        - name: "registrykey"
  volumeClaimTemplates:
  - metadata:
      name: data
      annotations:
        volume.beta.kubernetes.io/storage-class: "ceph-web" #引用ceph  class 的类
    spec:
      accessModes: [ "ReadWriteOnce" ]
      resources:
        requests:
          storage: 3Gi

部署 MySQL 集群

## 在 /etc/mariadb-cluster 目录下执行：
kubectl create -f .