描述网站开发的广告词,小程序开发公司米云,如何制作一个单页网站,注册一个公司需要哪些资料K8s-MySQL主从集群
引言
该案例代码均可从https://github.com/WeiXiao-Hyy/k8s_example 获取#xff0c;欢迎Star#xff01;
需求 一个“主从复制”的MySQL集群有一个主节点Master有多个从节点Slave从节点需要能水平扩展所以写操作只能在主节点上执行读操作可以在所有节点…K8s-MySQL主从集群
引言
该案例代码均可从https://github.com/WeiXiao-Hyy/k8s_example 获取欢迎Star
需求 一个“主从复制”的MySQL集群有一个主节点Master有多个从节点Slave从节点需要能水平扩展所以写操作只能在主节点上执行读操作可以在所有节点上执行 xtrabackup 案例 xtrabackup原理和实战案例参考xtrabackup docker实战
MySQL conf文件配置
由于statefulset生成的pod命名为mysql-0,mysql-1依次递增则可以取末尾的idx作为MySQL service-id.cnf文件中的mysqld属性。
spec:initContainers:- name: init-mysqlimage: mysql:5.7command:- bash- -c- |set -ex# Generate mysql server-id from pod ordinal index.[[ hostname ~ -([0-9])$ ]] || exit 1ordinal${BASH_REMATCH[1]}echo [mysqld] /mnt/conf.d/server-id.cnf# Add an offset to avoid reserved server-id0 value.echo server-id$((100 $ordinal)) /mnt/conf.d/server-id.cnf# Copy appropriate conf.d files from config-map to emptyDir.if [[ $ordinal -eq 0 ]]; thencp /mnt/config-map/master.cnf /mnt/conf.d/elsecp /mnt/config-map/slave.cnf /mnt/conf.d/fivolumeMounts:- name: confmountPath: /mnt/conf.d- name: config-mapmountPath: /mnt/config-mapHeadless Service创建
# Headless service for stable DNS entries of StatefulSet members.
apiVersion: v1
kind: Service
metadata:name: mysqllabels:app: mysql
spec:ports:- name: mysqlport: 3306clusterIP: Noneselector:app: mysql
---
# Client service for connecting to any MySQL instance for reads.
# For writes, you must instead connect to the master: mysql-0.mysql.
apiVersion: v1
kind: Service
metadata:name: mysql-readlabels:app: mysql
spec:ports:- name: mysqlport: 3306selector:app: mysql创建HeadLess-Service并且保证主节点的DNS为mysql-0.mysql其他从节点为mysql-read。 从节点复制同步数据
spec:initContainers:- name: clone-mysqlimage: gcr.io/google-samples/xtrabackup:1.0command:- bash- -c- |set -ex# Skip the clone if data already exists.[[ -d /var/lib/mysql/mysql ]] exit 0# Skip the clone on master (ordinal index 0).[[ hostname ~ -([0-9])$ ]] || exit 1ordinal${BASH_REMATCH[1]}[[ $ordinal -eq 0 ]] exit 0# Clone data from previous peer.ncat --recv-only mysql-$(($ordinal-1)).mysql 3307 | xbstream -x -C /var/lib/mysql# Prepare the backup.xtrabackup --prepare --target-dir/var/lib/mysqlvolumeMounts:- name: datamountPath: /var/lib/mysqlsubPath: mysql- name: confmountPath: /etc/mysql/conf.d流程图如下
从节点启动如何恢复数据 前提 xtrabackup_salve_info文件存在则说明该节点为从节点xtrabackup_binlog_info 文件存在则说明该节点为主节点从节点恢复数据启动主要需要获取两个字段MASTER_LOG_FILE和MASTER_LOG_POS
- name: xtrabackupimage: gcr.io/google-samples/xtrabackup:1.0ports:- name: xtrabackupcontainerPort: 3307command:- bash- -c- |set -excd /var/lib/mysql# Determine binlog position of cloned data, if any.if [[ -f xtrabackup_slave_info ]]; then# XtraBackup already generated a partial CHANGE MASTER TO query# because were cloning from an existing slave.mv xtrabackup_slave_info change_master_to.sql.in# Ignore xtrabackup_binlog_info in this case (its useless).rm -f xtrabackup_binlog_infoelif [[ -f xtrabackup_binlog_info ]]; then# Were cloning directly from master. Parse binlog position.[[ cat xtrabackup_binlog_info ~ ^(.*?)[[:space:]](.*?)$ ]] || exit 1rm xtrabackup_binlog_infoecho CHANGE MASTER TO MASTER_LOG_FILE${BASH_REMATCH[1]},\MASTER_LOG_POS${BASH_REMATCH[2]} change_master_to.sql.infi# Check if we need to complete a clone by starting replication.if [[ -f change_master_to.sql.in ]]; thenecho Waiting for mysqld to be ready (accepting connections)until mysql -h 127.0.0.1 -uroot -p$MYSQL_ROOT_PASSWORD -e SELECT 1; do sleep 1; doneecho Initializing replication from clone position# In case of container restart, attempt this at-most-once.mv change_master_to.sql.in change_master_to.sql.origmysql -h 127.0.0.1 -uroot -p$MYSQL_ROOT_PASSWORD EOF$(change_master_to.sql.orig),MASTER_HOSTmysql-0.mysql,MASTER_USERroot,MASTER_PASSWORD$MYSQL_ROOT_PASSWORD,MASTER_CONNECT_RETRY10;START SLAVE;EOFfi# Start a server to send backups when requested by peers.exec ncat --listen --keep-open --send-only --max-conns1 3307 -c \xtrabackup --backup --slave-info --streamxbstream --host127.0.0.1 --userrootvolumeMounts:- name: datamountPath: /var/lib/mysqlsubPath: mysql- name: confmountPath: /etc/mysql/conf.dresources:requests:cpu: 100mmemory: 100Mi流程图如下 等待MySQL服务启动操作until mysql -h 127.0.0.1 -uroot -pPASSWORD -e “Select 1”; do sleep 1; done
结果测试 K8s执行效果 MySQL客户端执行效果 主节点mysql-0.mysql写入从节点mysql-read读取。
