k8s-java-api 创建mysql集群
一:两种方式pvc挂在方式:
1:可以手动创建pvc 名字要符合 pvc-pod的名字(当时多副本的时候pod的名字=statefulset+数字,数字从 0开始)。
2;可以用pvc模板volumeClaimTemplates 自动创建pvc,这个不多说了,网上有很多资料
二:需要注意的点
我这边是用java 调用apiserver 创建的mysql集群,中间遇到的最大问题就是脚本执行不成功,下面说下解决思路:
1.将脚本粘贴到notepad++ ,编辑->文档格式转换->unix格式。
2.将转换后的脚本直接粘贴到command中就可以了。
下面是涉及的几个yaml文件内容:
当然官网的就可以直接用:
Run a Replicated Stateful Application | KubernetesThis page shows how to run a replicated stateful application using a StatefulSet controller. This application is a replicated MySQL database. The example topology has a single primary server and multiple replicas, using asynchronous row-based replication.Note: This is not a production configuration. MySQL settings remain on insecure defaults to keep the focus on general patterns for running stateful applications in Kubernetes. Before you begin You need to have a Kubernetes cluster, and the kubectl command-line tool must be configured to communicate with your cluster.https://kubernetes.io/docs/tasks/run-application/run-replicated-stateful-application/
configmap:
apiVersion: v1kind: ConfigMapmetadata: name: mysql labels: app: mysqldata: master.cnf: | # Apply this config only on the master. [mysqld] log-bin slave.cnf: | # Apply this config only on slaves. [mysqld] super-read-only
service:
# Headless service for stable DNS entries of StatefulSet members.apiVersion: v1kind: Servicemetadata: name: mysql labels: app: mysqlspec: 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 master: mysql-0.mysql.apiVersion: v1kind: Servicemetadata: name: mysql-read labels: app: mysqlspec: ports: - name: mysql port: 3306 selector: app: mysql
statefuleset:
apiVersion: apps/v1kind: StatefulSetmetadata: name: mysqlspec: selector: matchLabels: app: mysql serviceName: mysql replicas: 3 template: metadata: labels: app: mysql spec: initContainers: - name: init-mysql image: 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 [[ $ordinal -eq 0 ]]; then cp /mnt/config-map/master.cnf /mnt/conf.d/ else cp /mnt/config-map/slave.cnf /mnt/conf.d/ fi volumeMounts: - name: conf mountPath: /mnt/conf.d - name: config-map mountPath: /mnt/config-map - name: clone-mysql image: ist0ne/xtrabackup command: - bash - "-c" - | set -ex # Skip the clone if data already exists. [[ -d /var/lib/mysql/mysql ]] && exit 0 # Skip the clone on master (ordinal index 0). [[ `hostname` =~ -([0-9]+)$ ]] || exit 1 ordinal=${BASH_REMATCH[1]} [[ $ordinal -eq 0 ]] && exit 0 # Clone data from previous peer. ncat --recv-only mysql-$(($ordinal-1)).mysql 3307 | xbstream -x -C /var/lib/mysql # Prepare the backup. xtrabackup --prepare --target-dir=/var/lib/mysql volumeMounts: - name: data mountPath: /var/lib/mysql subPath: mysql - name: conf mountPath: /etc/mysql/conf.d containers: - name: mysql image: mysql:5.7 env: - name: MYSQL_ALLOW_EMPTY_PASSWORD value: "1" ports: - name: mysql containerPort: 3306 volumeMounts: - name: data mountPath: /var/lib/mysql subPath: mysql - name: conf mountPath: /etc/mysql/conf.d resources: requests: cpu: 500m memory: 1Gi livenessProbe: exec: command: ["mysqladmin", "ping"] initialDelaySeconds: 30 periodSeconds: 10 timeoutSeconds: 5 readinessProbe: exec: # Check we can execute queries over TCP (skip-networking is off). command: ["mysql", "-h", "127.0.0.1", "-e", "SELECT 1"] initialDelaySeconds: 5 periodSeconds: 2 timeoutSeconds: 1 - name: xtrabackup image: ist0ne/xtrabackup ports: - name: xtrabackup containerPort: 3307 command: - bash - "-c" - | set -ex cd /var/lib/mysql # Determine binlog position of cloned data, if any. if [[ -f xtrabackup_slave_info && "x$( 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 master. 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: data mountPath: /var/lib/mysql subPath: mysql - name: conf mountPath: /etc/mysql/conf.d resources: requests: cpu: 100m memory: 100Mi volumes: - name: conf emptyDir: {} - name: config-map configMap: name: mysql volumeClaimTemplates: - metadata: name: data spec: accessModes: ["ReadWriteOnce"] storageClassName: "managed-nfs-storage" resources: requests: storage: 10Gi