文章目录
1. 主从复制架构演变介绍
1.1 基本结构
（1）一主一从
（2）一主多从
（3）多级主从
（4）双主
（5）循环复制
1.2 高级应用架构演变
1.2.1 架构演变
读写分离: 读多写少的业务类型
Atlas , ProxySQL ,Maxscale .....
高可用: 解决业务主库宕机时,还能继续提供原有服务
架构：MHA,PXC,MGC,MGR,MIC(8.0)
分布式架构: 将逻辑单元拆分到不同的节点中,分担存储压力和业务压力.
Mycat,DBLE,Sharding-jdbc
NewSQL架构: 合久必分,分久必合.
TiDB , Polardb ,TDSQL
1.2.2 高可用架构标准评估
（1）单活:MMM架构——mysql-mmm（google）
（2）单活:MHA架构——mysql-master-ha（日本DeNa）,T-MHA
（3）多活:MGR ——5.7 新特性 MySQL Group replication(5.7.17) --->Innodb Cluster
（4）多活:MariaDB Galera Cluster架构,(PXC)Percona XtraDB Cluster、MySQL Cluster(Oracle rac)架构
99.9% 0.1% 365*24*60*0.001= 525.6 min
99.99% 0.01% 365*24*60*0.001= 52.56 min
99.999% 0.001% 365*24*60*0.001= 5.256 min
99.9999% 0.0001% 365*24*60*0.001= 0.5256 min
负载集群: 3个9
主备集群: 4个9 MHA
多活集群: 5个9 MySQL Cluster, MIC, PXC ,MGC
Real Application Cluster : Oracle RAC sysbase cluster
2. 高可用MHA架构搭建
2.1 架构工作原理
主库宕机处理过程
1. 监控节点 (通过配置文件获取所有节点信息)
系统,网络,SSH连接性
主从状态,重点是主库
2. 选主
(1) 如果判断从库(position或者GTID),数据有差异,最接近于Master的slave,成为备选主
(2) 如果判断从库(position或者GTID),数据一致,按照配置文件顺序,选主.
(3) 如果设定有权重(candidate_master=1),按照权重强制指定备选主.
1. 默认情况下如果一个slave落后master 100M的relay logs的话，即使有权重,也会失效.
2. 如果check_repl_delay=0的化,即使落后很多日志,也强制选择其为备选主
3. 数据补偿
(1) 当SSH能连接,从库对比主库GTID 或者position号,立即将二进制日志保存至各个从节点并且应用(save_binary_logs )
(2) 当SSH不能连接, 对比从库之间的relaylog的差异(apply_diff_relay_logs)
4. Failover
将备选主进行身份切换,对外提供服务
其余从库和新主库确认新的主从关系
5. 应用透明(VIP)
6. 故障切换通知(send_reprt)
7. 二次数据补偿(binlog_server)
8. 自愈自治(待开发...)
2.2 架构介绍:
1主2从GTID环境，master：db01 slave：db02 db03 ）：
MHA 高可用方案软件构成
Manager软件：选择一个从节点安装；线上环境单独机器安装；这里只做测试
Node软件：所有节点都要安装
2.3 MHA软件构成
Manager工具包主要包括以下几个工具：
masterha_manger 启动MHA
masterha_check_ssh 检查MHA的SSH配置状况
masterha_check_repl 检查MySQL复制状况
masterha_master_monitor 检测master是否宕机
masterha_check_status 检测当前MHA运行状态
masterha_master_switch 控制故障转移（自动或者手动）
masterha_conf_host 添加或删除配置的server信息
Node工具包主要包括以下几个工具：
这些工具通常由MHA Manager的脚本触发，无需人为操作
save_binary_logs 保存和复制master的二进制日志
apply_diff_relay_logs 识别差异的中继日志事件并将其差异的事件应用于其他的
purge_relay_logs 清除中继日志（不会阻塞SQL线程）
2.4 MHA环境搭建
2.4.1 环境规划:
主库: 51 node
从库:
52 node
53 node manager
2.4.2 准备环境（1主2从GTID）
已搭建
2.4.3 配置关键程序软连接【所有节点】
ln -s /usr/local/mysql57/bin/mysqlbinlog /usr/bin/mysqlbinlog
ln -s /usr/local/mysql57/bin/mysql /usr/bin/mysql
2.4.4 配置各节点互信【3个节点都要实现免密登录】
db01：
rm -rf /root/.ssh
ssh-keygen
cd /root/.ssh
mv id_rsa.pub authorized_keys
scp -r /root/.ssh 10.0.0.52:/root
scp -r /root/.ssh 10.0.0.53:/root
各节点验证
db01:
ssh 10.0.0.51 date
ssh 10.0.0.52 date
ssh 10.0.0.53 date
db02:
ssh 10.0.0.51 date
ssh 10.0.0.52 date
ssh 10.0.0.53 date
db03:
ssh 10.0.0.51 date
ssh 10.0.0.52 date
ssh 10.0.0.53 date
2.4.5 安装软件
下载mha软件
mha官网：https://code.google.com/archive/p/mysql-master-ha/
github下载地址：https://github.com/yoshinorim/mha4mysql-manager/wiki/Downloads
1、所有节点安装Node软件依赖包
yum install perl-DBD-MySQL -y
rpm -ivh mha4mysql-node-0.56-0.el6.noarch.rpm
2、在db01主库中创建mha需要的用户
grant all privileges on *.* to mha@'10.0.0.%' identified by 'mha';
3、Manager软件安装（db03）
yum install -y perl-Config-Tiny epel-release perl-Log-Dispatch perl-Parallel-ForkManager perl-Time-HiRes
rpm -ivh mha4mysql-manager-0.56-0.el6.noarch.rpm
2.4.6 配置文件准备(db03)
1、创建配置文件目录
mkdir -p /etc/mha
2、创建日志目录
mkdir -p /var/log/mha/app1
3、编辑mha配置文件
vim /etc/mha/app1.cnf #生产环境建议安装业务名取名
[server default]
manager_log=/var/log/mha/app1/manager #日志目录
manager_workdir=/var/log/mha/app1 #工作目录
master_binlog_dir=/data/binlog #主库二进制位置点
user=mha #管理员用户
password=mha
ping_interval=2 #每间隔2秒ping主机的心跳 会检测4次 8秒
repl_password=123 #复制密码
repl_user=repl #复制用户
ssh_user=root #传输数据和日志用的
[server1] #以下是各个节点的配置信息
hostname=10.0.0.51
port=3306
[server2]
hostname=10.0.0.52
port=3306
[server3]
hostname=10.0.0.53
port=3306
2.4.7 状态检查
互信检查:
[root@db03 ~]# masterha_check_ssh --conf=/etc/mha/app1.cnf
Fri Jan 3 11:23:58 2020 - [warning] Global configuration file /etc/masterha_default.cnf not found. Skipping.
Fri Jan 3 11:23:58 2020 - [info] Reading application default configuration from /etc/mha/app1.cnf..
Fri Jan 3 11:23:58 2020 - [info] Reading server configuration from /etc/mha/app1.cnf..
Fri Jan 3 11:23:58 2020 - [info] Starting SSH connection tests..
Fri Jan 3 11:23:59 2020 - [debug]
Fri Jan 3 11:23:58 2020 - [debug] Connecting via SSH from root@10.0.0.51(10.0.0.51:22) to root@10.0.0.52(10.0.0.52:22)..
Fri Jan 3 11:23:59 2020 - [debug] ok.
Fri Jan 3 11:23:59 2020 - [debug] Connecting via SSH from root@10.0.0.51(10.0.0.51:22) to root@10.0.0.53(10.0.0.53:22)..
Fri Jan 3 11:23:59 2020 - [debug] ok.
Fri Jan 3 11:24:00 2020 - [debug]
Fri Jan 3 11:23:59 2020 - [debug] Connecting via SSH from root@10.0.0.52(10.0.0.52:22) to root@10.0.0.51(10.0.0.51:22)..
Fri Jan 3 11:23:59 2020 - [debug] ok.
Fri Jan 3 11:23:59 2020 - [debug] Connecting via SSH from root@10.0.0.52(10.0.0.52:22) to root@10.0.0.53(10.0.0.53:22)..
Fri Jan 3 11:23:59 2020 - [debug] ok.
Fri Jan 3 11:24:01 2020 - [debug]
Fri Jan 3 11:23:59 2020 - [debug] Connecting via SSH from root@10.0.0.53(10.0.0.53:22) to root@10.0.0.51(10.0.0.51:22)..
Fri Jan 3 11:24:00 2020 - [debug] ok.
Fri Jan 3 11:24:00 2020 - [debug] Connecting via SSH from root@10.0.0.53(10.0.0.53:22) to root@10.0.0.52(10.0.0.52:22)..
Fri Jan 3 11:24:00 2020 - [debug] ok.
Fri Jan 3 11:24:01 2020 - [info] All SSH connection tests passed successfully.
主从状态检查:
[root@db03 ~]# masterha_check_repl --conf=/etc/mha/app1.cnf
Fri Jan 3 11:24:21 2020 - [warning] Global configuration file /etc/masterha_default.cnf not found. Skipping.
Fri Jan 3 11:24:21 2020 - [info] Reading application default configuration from /etc/mha/app1.cnf..
Fri Jan 3 11:24:21 2020 - [info] Reading server configuration from /etc/mha/app1.cnf..
Fri Jan 3 11:24:21 2020 - [info] MHA::MasterMonitor version 0.56.
Fri Jan 3 11:24:22 2020 - [info] GTID failover mode = 1
Fri Jan 3 11:24:22 2020 - [info] Dead Servers:
Fri Jan 3 11:24:22 2020 - [info] Alive Servers:
Fri Jan 3 11:24:22 2020 - [info] 10.0.0.51(10.0.0.51:3306)
Fri Jan 3 11:24:22 2020 - [info] 10.0.0.52(10.0.0.52:3306)
Fri Jan 3 11:24:22 2020 - [info] 10.0.0.53(10.0.0.53:3306)
Fri Jan 3 11:24:22 2020 - [info] Alive Slaves:
Fri Jan 3 11:24:22 2020 - [info] 10.0.0.52(10.0.0.52:3306) Version=5.7.26-log (oldest major version between slaves) log-bin:enabled
Fri Jan 3 11:24:22 2020 - [info] GTID ON
Fri Jan 3 11:24:22 2020 - [info] Replicating from 10.0.0.51(10.0.0.51:3306)
Fri Jan 3 11:24:22 2020 - [info] 10.0.0.53(10.0.0.53:3306) Version=5.7.26-log (oldest major version between slaves) log-bin:enabled
Fri Jan 3 11:24:22 2020 - [info] GTID ON
Fri Jan 3 11:24:22 2020 - [info] Replicating from 10.0.0.51(10.0.0.51:3306)
Fri Jan 3 11:24:22 2020 - [info] Current Alive Master: 10.0.0.51(10.0.0.51:3306)
Fri Jan 3 11:24:22 2020 - [info] Checking slave configurations..
Fri Jan 3 11:24:22 2020 - [info] read_only=1 is not set on slave 10.0.0.52(10.0.0.52:3306).
Fri Jan 3 11:24:22 2020 - [info] read_only=1 is not set on slave 10.0.0.53(10.0.0.53:3306).
Fri Jan 3 11:24:22 2020 - [info] Checking replication filtering settings..
Fri Jan 3 11:24:22 2020 - [info] binlog_do_db= , binlog_ignore_db=
Fri Jan 3 11:24:22 2020 - [info] Replication filtering check ok.
Fri Jan 3 11:24:22 2020 - [info] GTID (with auto-pos) is supported. Skipping all SSH and Node package checking.
Fri Jan 3 11:24:22 2020 - [info] Checking SSH publickey authentication settings on the current master..
Fri Jan 3 11:24:22 2020 - [info] HealthCheck: SSH to 10.0.0.51 is reachable.
Fri Jan 3 11:24:22 2020 - [info]
10.0.0.51(10.0.0.51:3306) (current master)
+--10.0.0.52(10.0.0.52:3306)
+--10.0.0.53(10.0.0.53:3306)
Fri Jan 3 11:24:22 2020 - [info] Checking replication health on 10.0.0.52..
Fri Jan 3 11:24:22 2020 - [info] ok.
Fri Jan 3 11:24:22 2020 - [info] Checking replication health on 10.0.0.53..
Fri Jan 3 11:24:22 2020 - [info] ok.
Fri Jan 3 11:24:22 2020 - [warning] master_ip_failover_script is not defined.
Fri Jan 3 11:24:22 2020 - [warning] shutdown_script is not defined.
Fri Jan 3 11:24:22 2020 - [info] Got exit code 0 (Not master dead).
MySQL Replication Health is OK.
2.4.8 启动MHA(db03)：
[root@db03 ~]# nohup masterha_manager --conf=/etc/mha/app1.cnf --remove_dead_master_conf --ignore_last_failover < /dev/null> /var/log/mha/app1/manager.log 2>&1 & [1] 2659
2.4.9 查看MHA状态
判断MHA的状态：OK则为正常
[root@db03 ~]# masterha_check_status --conf=/etc/mha/app1.cnf
app1 (pid:2659) is running(0:PING_OK), master:10.0.0.51
[root@db03 ~]# mysql -umha -pmha -h 10.0.0.51 -e "show variables like 'server_id'"
mysql: [Warning] Using a password on the command line interface can be insecure.
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| server_id | 51 |
+---------------+-------+
[root@db03 ~]# mysql -umha -pmha -h 10.0.0.52 -e "show variables like 'server_id'"
mysql: [Warning] Using a password on the command line interface can be insecure.
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| server_id | 52 |
+---------------+-------+
[root@db03 ~]# mysql -umha -pmha -h 10.0.0.53 -e "show variables like 'server_id'"
mysql: [Warning] Using a password on the command line interface can be insecure.
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| server_id | 53 |
+---------------+-------+
3. MHA 的工作原理
1. 通过masterha_manger脚本启动MHA高可用功能
2. 通过masterha_master_monitor监控主节点的状态,每ping_interval秒探测一次主库的心跳,一共检测4次.如过.4次都没通,认为主库宕机
3. 进行选主工作
算法一: 权重candidate_master=1
算法二: 判断日志量
算法三: 按照配置文件的顺序
4. 数据补偿
ssh能连: 各个从库通过(save_binary_logs)立即保存缺失部分binlog到/var/tmp/xxxx,并补偿数据.
ssh不能连:数据较少的从库,会通过apply_diff_relay_logs,计算差异,追平数据.
5. 通过masterha_master_switch 脚本切换.
所有从节点,stop slave; reset slave all;
s2节点,change master to s1 ,start slave
6. 调用masterha_conf_host脚本,从集群中将故障节点剔除.
7. manager 自杀.
缺点补足：
1. binlog server 日志冗余
2. 应用透明 vip漂移(可以选用keepalive,MHA自带vip功能-脚本)
3. 故障提醒
4. 自愈(待开发...),RDS,TDSQL都具备自愈能力.
4. MHA 扩展功能应用
4.1 MHA 的vip功能
(1) 准备脚本
[root@db03 ~]# cp master_ip_failover.txt /usr/local/bin/master_ip_failover
[root@db03 ~]# cd /usr/local/bin/
[root@db03 bin]# chmod +x master_ip_failover
[root@db03 bin]# dos2unix master_ip_failover
改配置文件:
[root@db03 bin]# vim master_ip_failover
...
my $vip = '10.0.0.55/24'; #VIP地址【没有在网络中使用的ip】
my $key = '1';
my $ssh_start_vip = "/sbin/ifconfig eth0:$key $vip"; #网卡名称
my $ssh_stop_vip = "/sbin/ifconfig eth0:$key down";
...
(2) manager配置文件修改
添加参数
[root@db03 bin]# vim /etc/mha/app1.cnf
master_ip_failover_script=/usr/local/bin/master_ip_failover
(3) 手动生成vip(主节点)
[root@db01 ~]# ifconfig eth0:1 10.0.0.55/24
(4) 在db03重启mha [先停止后启动]
masterha_stop --conf=/etc/mha/app1.cnf
nohup masterha_manager --conf=/etc/mha/app1.cnf --remove_dead_master_conf --ignore_last_failover < /dev/null > /var/log/mha/app1/manager.log 2>&1 &
(5)检测状态
masterha_check_status --conf=/etc/mha/app1.cnf
4.2 binlog server（db03）
4.2.1 参数：
vim /etc/mha/app1.cnf
[binlog1]
no_master=1 #1代表不作为选主时使用
hostname=10.0.0.53
master_binlog_dir=/data/mysql/binlog
4.2.2 创建binlog server专用目录并授权
mkdir -p /data/mysql/binlog
chown -R mysql.mysql /data/*
4.2.3 拉取主库binlog日志
cd /data/mysql/binlog
mysqlbinlog -R --host=10.0.0.51 --user=mha --password=mha --raw --stop-never mysql-bin.000001 &
4.2.4 重启MHA【先停再起】
masterha_stop --conf=/etc/mha/app1.cnf
nohup masterha_manager --conf=/etc/mha/app1.cnf --remove_dead_master_conf --ignore_last_failover < /dev/null > /var/log/mha/app1/manager.log 2>&1 &
4.3 邮件提醒
1. 参数：
report_script=/usr/local/bin/send
2. 准备邮件脚本
send_report
(1)准备发邮件的脚本(上传 email_2019-最新.zip中的脚本，到/usr/local/bin/中并给x权限)
(2)将准备好的脚本添加到mha配置文件中,让其调用
3. 修改manager配置文件，调用邮件脚本
vi /etc/mha/app1.cnf
report_script=/usr/local/bin/send
4. 停止MHA
masterha_stop --conf=/etc/mha/app1.cnf
5. 开启MHA
nohup masterha_manager --conf=/etc/mha/app1.cnf --remove_dead_master_conf --ignore_last_failover < /dev/null > /var/log/mha/app1/manager.log 2>&1 &
6. 关闭主库,看警告邮件
6.1 检测VIP是否存在
inet 10.0.0.55/24 brd 10.0.0.255 scope global secondary eth0:1
6.2 关闭主库mysql
pkill mysqld
6.3 邮件脚本：
[root@db03 bin]# cat /usr/local/bin/testpl
#!/bin/bash
/usr/local/bin/sendEmail -o tls=no -f 发件人邮箱 -t 991540698@qq.com -s smtp.126.com:25 -xu 用户名 -xp 密码 -u "MHA Waring" -m "YOUR MHA MAY BE FAILOVER" &>/tmp/sendmail.log
--------------------------------------------------------------------------------------
--------------------------------------------------------------------------------------
7. MHA 故障修复：
故障：VIP已飘逸至db02
inet 10.0.0.55/24 brd 10.0.0.255 scope global secondary eth0:1
db03 [(none)]>show slave status \G
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 10.0.0.52
Master_User: repl
Master_Port: 3306
[root@db03 bin]# masterha_check_status --conf=/etc/mha/app1.cnf
NOT RUNNING
故障修复思路：
7.1. 恢复故障节点db01
/etc/init.d/mysqld start
7.2. 修复主从 【db01操作】
将db01 加入到主从环境中作为从库角色
change master to
master_host='10.0.0.52',
master_user='repl',
master_password='123' ,
MASTER_AUTO_POSITION=1;
start slave;
7.3. 修复binlog_server(db03)
[root@db03 binlog]# cd /data/mysql/binlog/
[root@db03 binlog]# rm -rf *
从现有的主库拉取日志
[root@db03 binlog]# mysqlbinlog -R --host=10.0.0.52 --user=mha --password=mha --raw --stop-never mysql-bin.000001 &
7.4. 检查主库vip
[root@db02 ~]# ifconfig -a
eth0:1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 10.0.0.55 netmask 255.255.255.0 broadcast 10.0.0.255
ether 00:0c:29:18:0c:cf txqueuelen 1000 (Ethernet)
7.5. 检查配置文件节点信息(db03)
[root@db03 bin]# vim /etc/mha/app1.cnf
.....
[server1]
hostname=10.0.0.51
port=3306
[server2]
hostname=10.0.0.52
port=3306
[server3]
hostname=10.0.0.53
port=3306
.....
7.6. 状态检查
互信检查
masterha_check_ssh --conf=/etc/mha/app1.cnf
主从检查
masterha_check_repl --conf=/etc/mha/app1.cnf
7.7. 启动MHA
nohup masterha_manager --conf=/etc/mha/app1.cnf --remove_dead_master_conf --ignore_last_failover < /dev/null > /var/log/mha/app1/manager.log 2>&1 &
7.8 健康检测
[root@db03 bin]# masterha_check_status --conf=/etc/mha/app1.cnf
app1 (pid:11716) is running(0:PING_OK), master:10.0.0.52
7.9 至此，故障修复完毕
5. 读写分离Atlas+MHA应用
5.1 介绍
Atlas是由 Qihoo 360, Web平台部基础架构团队开发维护的一个基于MySQL协议的数据中间层项目。
它是在mysql-proxy 0.8.2版本的基础上，对其进行了优化，增加了一些新的功能特性。
360内部使用Atlas运行的mysql业务，每天承载的读写请求数达几十亿条。
下载地址
https://github.com/Qihoo360/Atlas/releases
注意：
1、Atlas只能安装运行在64位的系统上
2、Centos 5.X安装 Atlas-XX.el5.x86_64.rpm，Centos 6.X安装Atlas-XX.el6.x86_64.rpm。
3、后端mysql版本应大于5.1，建议使用Mysql 5.6以上
5.2 安装配置【db03】
1. 安装
yum install -y Atlas*
cd /usr/local/mysql-proxy/conf
mv test.cnf test.cnf.bak
2. 编写配置文件
vi test.cnf
[mysql-proxy]
admin-username = user #管理用户
admin-password = pwd #管理密码
proxy-backend-addresses = 10.0.0.55:3306 #写的节点MHA VIP
proxy-read-only-backend-addresses = 10.0.0.51:3306,10.0.0.53:3306 #从节点
pwds = repl:3yb5jEku5h4=,mha:O2jBXONX098= #后端数据库节点真实的用户和密码
daemon = true #后台运行
keepalive = true #是否坚持心跳
event-threads = 8 #并发连接数
log-level = message
log-path = /usr/local/mysql-proxy/log
sql-log=ON #记录atlas的sql语句
proxy-address = 0.0.0.0:33060 #对外服务端口
admin-address = 0.0.0.0:2345 #管理服务端口
charset=utf8 #字符集
3. 启动atlas
/usr/local/mysql-proxy/bin/mysql-proxyd test start
[root@db03 bin]# netstat -lntup |grep proxy
tcp 0 0 0.0.0.0:33060 0.0.0.0:* LISTEN 12930/mysql-proxy
tcp 0 0 0.0.0.0:2345 0.0.0.0:* LISTEN 12930/mysql-proxy
PS：如果在MySQL8.0环境中，不要使用33060端口，会和8.0系统的一个X协议端口冲突；
5.3 Atlas功能测试【db03】
1、测试读操作：
mysql -umha -pmha -h 10.0.0.53 -P 33060
db03 [(none)]>select @@server_id;
结果显示都在51和53 从节点
2、测试写操作：
mysql> begin;select @@server_id;commit; #主节点
5.4 Atlas的管理
1、登录后端管理
[root@db03 ~]# mysql -uuser -ppwd -h10.0.0.53 -P2345
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 1
Server version: 5.0.99-agent-admin
Copyright (c) 2000, 2019, Oracle and/or its affiliates. All rights reserved.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
2、查看帮助信息
db03 [(none)]>select * from help;
+----------------------------+---------------------------------------------------------+
| SELECT * FROM help | shows this help |
| SELECT * FROM backends | lists the backends and their state |
| SET OFFLINE $backend_id | offline backend server, $backend_id is backend_ndx's id |
| SET ONLINE $backend_id | online backend server, ... |
| ADD MASTER $backend | example: "add master 127.0.0.1:3306", ... |
| ADD SLAVE $backend | example: "add slave 127.0.0.1:3306", ... |
| REMOVE BACKEND $backend_id | example: "remove backend 1", ... |
| SELECT * FROM clients | lists the clients |
| ADD CLIENT $client | example: "add client 192.168.1.2", ... |
| REMOVE CLIENT $client | example: "remove client 192.168.1.2", ... |
| SELECT * FROM pwds | lists the pwds |
| ADD PWD $pwd | example: "add pwd user:raw_password", ... |
| ADD ENPWD $pwd | example: "add enpwd user:encrypted_password", ... |
| REMOVE PWD $pwd | example: "remove pwd user", ... |
| SAVE CONFIG | save the backends to config file |
| SELECT VERSION | display the version of Atlas |
+----------------------------+-----------------------------------
3、查询后端所有节点信息
db03 [(none)]>SELECT * FROM backends;
+-------------+----------------+-------+------+
| backend_ndx | address | state | type |
+-------------+----------------+-------+------+
| 1 | 10.0.0.55:3306 | up | rw |
| 2 | 10.0.0.51:3306 | up | ro |
| 3 | 10.0.0.53:3306 | up | ro |
+-------------+----------------+-------+------+
3 rows in set (0.00 sec)
4、关闭某个节点服务
db03 [(none)]>SET OFFLINE 3;
+-------------+----------------+---------+------+
| backend_ndx | address | state | type |
+-------------+----------------+---------+------+
| 3 | 10.0.0.53:3306 | offline | ro |
+-------------+----------------+---------+------+
1 row in set (0.00 sec)
5、启动节点
db03 [(none)]>SET ONLINE 3;
+-------------+----------------+---------+------+
| backend_ndx | address | state | type |
+-------------+----------------+---------+------+
| 3 | 10.0.0.53:3306 | unknown | ro |
+-------------+----------------+---------+------+
1 row in set (0.00 sec)
6、删除一个节点
db03 [(none)]>REMOVE BACKEND 3;
Empty set (0.00 sec)
db03 [(none)]>SELECT * FROM backends;
+-------------+----------------+-------+------+
| backend_ndx | address | state | type |
+-------------+----------------+-------+------+
| 1 | 10.0.0.55:3306 | up | rw |
| 2 | 10.0.0.51:3306 | up | ro |
+-------------+----------------+-------+------+
2 rows in set (0.00 sec)
PS：节点没有down掉，只是atlas服务里没有了它
7、添加节点
db03 [(none)]>ADD SLAVE 10.0.0.53:3306;
Empty set (0.00 sec)
db03 [(none)]>SELECT * FROM backends;
+-------------+----------------+-------+------+
| backend_ndx | address | state | type |
+-------------+----------------+-------+------+
| 1 | 10.0.0.55:3306 | up | rw |
| 2 | 10.0.0.51:3306 | up | ro |
| 3 | 10.0.0.53:3306 | up | ro |
+-------------+----------------+-------+------+
3 rows in set (0.00 sec)
8、查看标识后端数据库管理用户的信息
db03 [(none)]>SELECT * FROM pwds;
+----------+--------------+
| username | password |
+----------+--------------+
| repl | 3yb5jEku5h4= |
| mha | O2jBXONX098= |
+----------+--------------+
2 rows in set (0.00 sec)
9、添加用户
db02 [(none)]>grant all on *.* to test@'10.0.0.%' identified by '123';
Query OK, 0 rows affected, 1 warning (0.00 sec)
db03 [(none)]>ADD PWD test:123;
Empty set (0.00 sec)
db03 [(none)]>SELECT * FROM pwds;
+----------+--------------+
| username | password |
+----------+--------------+
| repl | 3yb5jEku5h4= |
| mha | O2jBXONX098= |
| test | 3yb5jEku5h4= |
+----------+--------------+
3 rows in set (0.00 sec)
PS：添加用户需要两步：
（1）后台数据库
（2）atlas里添加；可以看出自动加密
只有满足这两步，Atlas才可以正常调用
以上操作只是临时的，永久配置需要执行“SAVE CONFIG” 立即将配置刷新到配置文件；下次登录继续存在
