k8s实践之mysql集群搭建

apiVersion: apps/v1 kind: StatefulSet metadata: name: mysql spec: selector: matchLabels: app: mysql app.kubernetes.io/name: mysql serviceName: mysql replicas: 3 template: metadata: labels: app: mysql app.kubernetes.io/name: 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 [[ $ordinal -eq 0 ]]; then cp /mnt/config-map/primary.cnf /mnt/conf.d/ else cp /mnt/config-map/replica.cnf /mnt/conf.d/ fi volumeMounts: - name: conf mountPath: /mnt/conf.d - name: config-map mountPath: /mnt/config-map - name: clone-mysql image: gcr.io/google-samples/xtrabackup:1.0 command: - bash - "-c" - | set -ex # Skip the clone if data already exists. [[ -d /var/lib/mysql/mysql ]] && exit 0 # Skip the clone on primary (ordinal index 0). [[ `hostname` =~ -([0-9]+)$ ]] || exit 1 ordinal=${BASH_REMATCH[1]} [[ $ordinal -eq 0 ]] && exit 0 # Clone data from previous peer. ncat --recv-only mysql-$(($ordinal-1)).mysql 3307 | xbstream -x -C /var/lib/mysql # Prepare the backup. xtrabackup --prepare --target-dir=/var/lib/mysql volumeMounts: - name: data mountPath: /var/lib/mysql subPath: mysql - name: conf mountPath: /etc/mysql/conf.d containers: - name: mysql image: mysql:5.7 env: - name: MYSQL_ALLOW_EMPTY_PASSWORD value: "1" ports: - name: mysql containerPort: 3306 volumeMounts: - name: data mountPath: /var/lib/mysql subPath: mysql - name: conf mountPath: /etc/mysql/conf.d resources: requests: cpu: 500m memory: 1Gi livenessProbe: exec: command: ["mysqladmin", "ping"] initialDelaySeconds: 30 periodSeconds: 10 timeoutSeconds: 5 readinessProbe: exec: # Check we can execute queries over TCP (skip-networking is off). command: ["mysql", "-h", "127.0.0.1", "-e", "SELECT 1"] initialDelaySeconds: 5 periodSeconds: 2 timeoutSeconds: 1 - name: xtrabackup image: gcr.io/google-samples/xtrabackup:1.0 ports: - name: xtrabackup containerPort: 3307 command: - bash - "-c" - | set -ex cd /var/lib/mysql # Determine binlog position of cloned data, if any. if [[ -f xtrabackup_slave_info && "x$(<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: 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: local-storage resources: requests: storage: 1Gi