博客作业第五周-mysql主从复制、高可用性、运维自动化ansible

1、如果主节点已经运行了一段时间，且有大量数据时，如何配置并启动slave节点

实验环境：master： centos8 10.0.0.68 mariadb-10.3.17
slave： centos8 10.0.0.58 mariadb-10.3.17
两台主机分别安装mariadb

[root@master ~]#yum -y install mariadb-server
[root@slave ~]#yum -y install mariadb-server

master配置

(1)为主节点指定server-id和开启二进制日志，启动服务

[root@master ~]#vim /etc/my.cnf.d/mariadb-server.cnf 

[server]

# this is only for the mysqld standalone daemon
# Settings user and group are ignored when systemd is used.
# If you need to run mysqld under a different user or group,
# customize your systemd unit file for mysqld/mariadb according to the
# instructions in http://fedoraproject.org/wiki/Systemd
[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
log-error=/var/log/mariadb/mariadb.log
pid-file=/run/mariadb/mariadb.pid
server-id=68         #指定id
log_bin				#开启二进制日志

#
# * Galera-related settings
#
[galera]
"/etc/my.cnf.d/mariadb-server.cnf" 56L, 1478C

[root@master ~]#systemctl start mariadb.service 

（2）模拟数据库运行一段时间导入测试数据库

[root@master ~]#mysql < hellodb_innodb.sql 
**MariaDB [(none)]> show databases;
+--------------------+
| Database           |
+--------------------+
| hellodb            |
| information_schema |
| mysql              |
| performance_schema |
+--------------------+
4 rows in set (0.000 sec)

修改表行

**MariaDB [hellodb]> update students set age=25,gender='F' where stuid=25;
Query OK, 1 row affected (0.003 sec)
Rows matched: 1  Changed: 1  Warnings: 0

MariaDB [hellodb]> select * from students;
+-------+---------------+-----+--------+---------+-----------+
| StuID | Name          | Age | Gender | ClassID | TeacherID |
+-------+---------------+-----+--------+---------+-----------+
|     1 | Shi Zhongyu   |  22 | M      |       2 |         3 |
|     2 | Shi Potian    |  22 | M      |       1 |         7 |
|     3 | Xie Yanke     |  53 | M      |       2 |        16 |
|     4 | Ding Dian     |  32 | M      |       4 |         4 |
|     5 | Yu Yutong     |  26 | M      |       3 |         1 |
|     6 | Shi Qing      |  46 | M      |       5 |      NULL |
|     7 | Xi Ren        |  19 | F      |       3 |      NULL |
|     8 | Lin Daiyu     |  17 | F      |       7 |      NULL |
|     9 | Ren Yingying  |  20 | F      |       6 |      NULL |
|    10 | Yue Lingshan  |  19 | F      |       3 |      NULL |
|    11 | Yuan Chengzhi |  23 | M      |       6 |      NULL |
|    12 | Wen Qingqing  |  19 | F      |       1 |      NULL |
|    13 | Tian Boguang  |  33 | M      |       2 |      NULL |
|    14 | Lu Wushuang   |  17 | F      |       3 |      NULL |
|    15 | Duan Yu       |  19 | M      |       4 |      NULL |
|    16 | Xu Zhu        |  21 | M      |       1 |      NULL |
|    17 | Lin Chong     |  25 | M      |       4 |      NULL |
|    18 | Hua Rong      |  23 | M      |       7 |      NULL |
|    19 | Xue Baochai   |  18 | F      |       6 |      NULL |
|    20 | Diao Chan     |  19 | F      |       7 |      NULL |
|    21 | Huang Yueying |  22 | F      |       6 |      NULL |
|    22 | Xiao Qiao     |  20 | F      |       1 |      NULL |
|    23 | Ma Chao       |  23 | M      |       4 |      NULL |
|    24 | Xu Xian       |  27 | M      |    NULL |      NULL |
|    25 | Sun Dasheng   |  25 | F      |    NULL |      NULL |
+-------+---------------+-----+--------+---------+-----------+
25 rows in set (0.000 sec)
**

（3）生产中遇到运行一段时间的数据库，先查看当前二进制日志的位置（show master logs;），然后对数据库进行完全备份

**MariaDB [hellodb]> show master logs;
+--------------------+-----------+
| Log_name           | File_size |
+--------------------+-----------+
| mariadb-bin.000001 |     28198 |
| mariadb-bin.000002 |      9157 |
+--------------------+-----------+
2 rows in set (0.000 sec)
**

[root@master ~]#mysqldump -A --single-transaction --master-data=1 -F > /backup/all.sql

查看备份文件，003日志389往后即需要同步的内容

[root@master ~]#vim /backup/all.sql 

/*!40101 SET @OLD_SQL_MODE=@@SQL_MODE, SQL_MODE='NO_AUTO_VALUE_ON_ZERO' */;
/*!40111 SET @OLD_SQL_NOTES=@@SQL_NOTES, SQL_NOTES=0 */;

--
-- Position to start replication or point-in-time recovery from
--

CHANGE MASTER TO MASTER_LOG_FILE='mariadb-bin.000003', MASTER_LOG_POS=389;  #改行记录备份时二进制日志位置

--
-- GTID to start replication from
--

-- SET GLOBAL gtid_slave_pos='0-68-80';

--
-- Current Database: `hellodb`
--

CREATE DATABASE /*!32312 IF NOT EXISTS*/ `hellodb` /*!40100 DEFAULT CHARACTER SET utf8 */;

USE `hellodb`;

--
-- Table structure for table `classes`
--

DROP TABLE IF EXISTS `classes`;
/*!40101 SET @saved_cs_client     = @@character_set_client */;
/*!40101 SET character_set_client = utf8 */;
CREATE TABLE `classes` (
  `ClassID` tinyint(3) unsigned NOT NULL AUTO_INCREMENT,
  `Class` varchar(100) DEFAULT NULL,
  `NumOfStu` smallint(5) unsigned DEFAULT NULL,

（4）创建有复制权限的账号

MariaDB [(none)]> grant replication slave on *.* to repluser@'10.0.0.%' identified by '123456';
Query OK, 0 rows affected (0.001 sec)

slave配置

（1）修改server-id 启动服务

[root@slave ~]#vim /etc/my.cnf.d/mariadb-server.cnf 

#
# These groups are read by MariaDB server.
# Use it for options that only the server (but not clients) should see
#
#
# These groups are read by MariaDB server.
# Use it for options that only the server (but not clients) should see
#
# See the examples of server my.cnf files in /usr/share/mysql/
#

# this is read by the standalone daemon and embedded servers
[server]

# this is only for the mysqld standalone daemon
# Settings user and group are ignored when systemd is used.
# If you need to run mysqld under a different user or group,
# customize your systemd unit file for mysqld/mariadb according to the
# instructions in http://fedoraproject.org/wiki/Systemd
[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
log-error=/var/log/mariadb/mariadb.log
pid-file=/run/mariadb/mariadb.pid
server-id=58      #指定id

（2）将主节点的完全备份文件拷贝到从节点，进行编辑添加信息，添加信息分别为：要复制的主节点IP地址、用于复制的用户名、密码、数据库端口号

[root@master ~]#scp /backup/all.sql [email protected]:/root
The authenticity of host '10.0.0.58 (10.0.0.58)' can't be established.
ECDSA key fingerprint is SHA256:2At7o6y8rVcjVAyXEeyB5nXI7CCJvPe+0QYOi8Y7AvU.
Are you sure you want to continue connecting (yes/no/[fingerprint])? yes
Warning: Permanently added '10.0.0.58' (ECDSA) to the list of known hosts.
[email protected]'s password: 
all.sql                                                                                                                                   100%  476KB  40.5MB/s   00:00    

[root@slave ~]#vim all.sql 

-- MySQL dump 10.17  Distrib 10.3.17-MariaDB, for Linux (x86_64)
--
-- Host: localhost    Database: 
-- ------------------------------------------------------
-- Server version       10.3.17-MariaDB-log

/*!40101 SET @OLD_CHARACTER_SET_CLIENT=@@CHARACTER_SET_CLIENT */;
/*!40101 SET @OLD_CHARACTER_SET_RESULTS=@@CHARACTER_SET_RESULTS */;
/*!40101 SET @OLD_COLLATION_CONNECTION=@@COLLATION_CONNECTION */;
/*!40101 SET NAMES utf8mb4 */;
/*!40103 SET @OLD_TIME_ZONE=@@TIME_ZONE */;
/*!40103 SET TIME_ZONE='+00:00' */;
/*!40014 SET @OLD_UNIQUE_CHECKS=@@UNIQUE_CHECKS, UNIQUE_CHECKS=0 */;
/*!40014 SET @OLD_FOREIGN_KEY_CHECKS=@@FOREIGN_KEY_CHECKS, FOREIGN_KEY_CHECKS=0 */;
/*!40101 SET @OLD_SQL_MODE=@@SQL_MODE, SQL_MODE='NO_AUTO_VALUE_ON_ZERO' */;
/*!40111 SET @OLD_SQL_NOTES=@@SQL_NOTES, SQL_NOTES=0 */;

--
-- Position to start replication or point-in-time recovery from
--
CHANGE MASTER TO
  MASTER_HOST='10.0.0.68',
  MASTER_USER='repluser',
  MASTER_PASSWORD='123456',
  MASTER_PORT=3306,
 MASTER_LOG_FILE='mariadb-bin.000003', MASTER_LOG_POS=389;

（3）将修改好的文件导入到数据库中

[root@slave ~]#mysql < all.sql 

（4）查看复制状态

MariaDB [hellodb]> show slave status\G;
*************************** 1. row ***************************
                Slave_IO_State: 
                   Master_Host: 10.0.0.68
                   Master_User: repluser
                   Master_Port: 3306
                 Connect_Retry: 60
               Master_Log_File: mariadb-bin.000003
           Read_Master_Log_Pos: 389
                Relay_Log_File: mariadb-relay-bin.000001
                 Relay_Log_Pos: 4
         Relay_Master_Log_File: mariadb-bin.000003
              Slave_IO_Running: No
             Slave_SQL_Running: No
               Replicate_Do_DB: 
           Replicate_Ignore_DB: 
            Replicate_Do_Table: 
        Replicate_Ignore_Table: 
       Replicate_Wild_Do_Table: 
   Replicate_Wild_Ignore_Table: 
                    Last_Errno: 0
                    Last_Error: 
                  Skip_Counter: 0
           Exec_Master_Log_Pos: 389
               Relay_Log_Space: 256
               Until_Condition: None
                Until_Log_File: 
                 Until_Log_Pos: 0
            Master_SSL_Allowed: No
            Master_SSL_CA_File: 
            Master_SSL_CA_Path: 
               Master_SSL_Cert: 
             Master_SSL_Cipher: 
                Master_SSL_Key: 
         Seconds_Behind_Master: NULL
 Master_SSL_Verify_Server_Cert: No
                 Last_IO_Errno: 0

（5）主节点服务器修改数据查看从节点是否能同步

主节点数据库修改

MariaDB [hellodb]> update students set age=30,gender='M' where stuid=25;
Query OK, 1 row affected (0.002 sec)
Rows matched: 1  Changed: 1  Warnings: 0

查看从节点发现数据已经同步

MariaDB [hellodb]> select * from students;
+-------+---------------+-----+--------+---------+-----------+
| StuID | Name          | Age | Gender | ClassID | TeacherID |
+-------+---------------+-----+--------+---------+-----------+
|     1 | Shi Zhongyu   |  22 | M      |       2 |         3 |
|     2 | Shi Potian    |  22 | M      |       1 |         7 |
|     3 | Xie Yanke     |  53 | M      |       2 |        16 |
|     4 | Ding Dian     |  32 | M      |       4 |         4 |
|     5 | Yu Yutong     |  26 | M      |       3 |         1 |
|     6 | Shi Qing      |  46 | M      |       5 |      NULL |
|     7 | Xi Ren        |  19 | F      |       3 |      NULL |
|     8 | Lin Daiyu     |  17 | F      |       7 |      NULL |
|     9 | Ren Yingying  |  20 | F      |       6 |      NULL |
|    10 | Yue Lingshan  |  19 | F      |       3 |      NULL |
|    11 | Yuan Chengzhi |  23 | M      |       6 |      NULL |
|    12 | Wen Qingqing  |  19 | F      |       1 |      NULL |
|    13 | Tian Boguang  |  33 | M      |       2 |      NULL |
|    14 | Lu Wushuang   |  17 | F      |       3 |      NULL |
|    15 | Duan Yu       |  19 | M      |       4 |      NULL |
|    16 | Xu Zhu        |  21 | M      |       1 |      NULL |
|    17 | Lin Chong     |  25 | M      |       4 |      NULL |
|    18 | Hua Rong      |  23 | M      |       7 |      NULL |
|    19 | Xue Baochai   |  18 | F      |       6 |      NULL |
|    20 | Diao Chan     |  19 | F      |       7 |      NULL |
|    21 | Huang Yueying |  22 | F      |       6 |      NULL |
|    22 | Xiao Qiao     |  20 | F      |       1 |      NULL |
|    23 | Ma Chao       |  23 | M      |       4 |      NULL |
|    24 | Xu Xian       |  27 | M      |    NULL |      NULL |
|    25 | Sun Dasheng   |  30 | M      |    NULL |      NULL |
+-------+---------------+-----+--------+---------+-----------+
25 rows in set (0.001 sec)

2、当master服务器宕机，提升一个slave成为新的maste

如遇主服务器挂掉，有两个从节点，查看从节点复制状态，哪个值大哪个为新主节点，成为主服务需要开启二进制日志，关闭read-only选项重启数据库服务
（1）比较以下值哪个较大，哪个为新主

（2）选定新主服务器开启二进制日志，关闭read-only，重启数据库服务
（3）选定新主服务器关闭从节点复制的两个线程

（4）选定新主服务器删除从节点信息

（5）在另一台未选中为主服务器关闭从节点线程，清理从节点信息，重新建立主节点复制信息
（6）查看新主节点当前二进制日志位置，在新从节点创建复制

（7）从节点创建复制，启动线程

3、通过 MHA 0.58 搭建一个数据库集群结构

一、MHA功能介绍

MHA（Master HA）是一款开源的 MySQL 的高可用程序，它为 MySQL 主从复制架构提供了 automating master failover 功能。MHA 在监控到 master 节点故障时，会提升其中拥有最新数据的 slave 节点成为新的master 节点，在此期间，MHA 会通过于其它从节点获取额外信息来避免一致性方面的问题。MHA 还提供了 master 节点的在线切换功能，即按需切换 master/slave 节点。

二、实验环境

四台主机
10.0.0.47	centos7	                 MHA管理端
10.0.0.68	centos8	   mysql5.7      master
10.0.0.58	centos8	   mysql5.7      slave1
10.0.0.48	centos8	   mysql5.7      slave2

三、实验步骤

（1）管理端10.0.0.47安装两个包，提前将rpm包拷贝到服务器上

[root@Centos7 ~]# yum -y install mha4mysql-node-0.58-0.el7.centos.noarch.rpm 
[root@Centos7 ~]# yum -y install mha4mysql-manager-0.58-0.el7.centos.noarch.rpm 

（2）所有节点安装 mha4mysql-node-0.58-0.el7.centos.noarch.rpm包

[root@centos8 ~]#yum -y install mha4mysql-node-0.58-0.el7.centos.noarch.rpm

（3）在所有节点实现相互之间ssh key验证

[root@MHA-manager ~]# ssh-keygen 
Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa): 
/root/.ssh/id_rsa already exists.
Overwrite (y/n)? y
Enter passphrase (empty for no passphrase): 
Enter same passphrase again: 
Your identification has been saved in /root/.ssh/id_rsa.
Your public key has been saved in /root/.ssh/id_rsa.pub.
The key fingerprint is:
SHA256:ZcqwWG++dnbfk8EInqznpWoOJTqpCx5n5eJl7BJW03U root@MHA-manager
The key's randomart image is:
+---[RSA 2048]----+
|                 |
|         . E     |
|      + . +      |
|     = * + .     |
|    o.o.S.o o o  |
|   o+ ooo  + . o |
| o.+.O .. .  .  o|
|. *.* . o+o.+  + |
| . +o. .+=++ .. o|
+----[SHA256]-----+
[root@MHA-manager ~]# ssh-copy-id 127.0.0.1
/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/root/.ssh/id_rsa.pub"
The authenticity of host '127.0.0.1 (127.0.0.1)' can't be established.
ECDSA key fingerprint is SHA256:IHxJ9vqEMp/UwtZ034seLyuNP0D0By5u/O7iBCM2Cik.
ECDSA key fingerprint is MD5:72:b0:4c:7e:54:e3:92:e5:d0:05:ec:57:2c:7b:31:c3.
Are you sure you want to continue connecting (yes/no)? yes
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
[email protected]'s password: 

Number of key(s) added: 1

Now try logging into the machine, with:   "ssh '127.0.0.1'"
and check to make sure that only the key(s) you wanted were added.
[root@MHA-manager ~]# rsync -a .ssh 10.0.0.48:/root/
root@MHA-manager ~]# rsync -a .ssh 10.0.0.58:/root/
[root@MHA-manager ~]# rsync -a .ssh 10.0.0.68:/root/

（4）在管理节点建立配置文件

[root@MHA-manager ~]# mkdir /etc/mastermha
[root@MHA-manager ~]# vim /etc/mastermha/app1.cnf
[server default]
user=mhauser #用于远程链接MySQL所有节点的用户，需要有管理员权限
password=123456
manager_workdir=/data/mastermha/app1/  #该目录会自动生成
manager_log=/data/mastermha/app1/manager.log
remote_workdir=/data/mastermha/app1/
ssh_user=root   #用于实现远程ssh基于key验证的连接
repl_user=repluser #主从复制的用户
repl_password=magedu
ping_interval=1 #健康检查的时间间隔
master_ip_failover_script=/usr/local/bin/master_ip_failover #切换VIP的perl脚本
report_script=/usr/local/bin/sendmail.sh #报警脚本
check_repl_delay=0 #默认slave中从库落后主库relaylog超过100M，主库不会选择这个从库为新的master，因为这个从库>进行恢复需要很长的时间。通过这个参数，mha触发主从切换的时候会忽略复制的延时，对于设置candidate_master=1的从>库非常有用，确保这个从库一定能成为最新的master
master_binlog_dir=/data/mysql/ #指定二进制日志存放的目录，mha4mysql-manager-0.58版本必须指定，之前的不需要
[server1]
hostname=10.0.0.68
candidate_master=1  
[server2]
hostname=10.0.0.58
candidate_master=1  #设置为优先候选master，即使不是集群中事件最新的slave,也会优先当
master
[server3]
hostname=10.0.0.48

在管理节点安装mailx软件包，准备.mailrc文件，准备两个相关脚本

[root@Centos7 ~]# yum -y install mailx.x86_64 
[root@Centos7 ~]# cat .mailrc 
set from=[email protected]
set smtp=smtp.139.com
set smtp-auth-user=13593386981
set smtp-auth-password=GaoJinZhou00
set smtp-auth=login
set ssl-verify=ignore
[root@Centos7 ~]# chmod +x /usr/local/bin/sendmail.sh 
[root@Centos7 ~]# cat /usr/local/bin/master_ip_failover 
#!/usr/bin/env perl
use strict;
use warnings FATAL=> 'all';
use Getopt::Long;
my(
$command, $ssh_user, $orig_master_host, $orig_master_ip, $orig_master_port,$new_master_host, $new_master_ip, $new_master_port);
my $vip = '10.0.0.100/24';
my $gateway = '10.0.0.2';
my $interface = 'eth0';
my $key = "1";
my $ssh_start_vip = "/sbin/ifconfig $interface:$key $vip;/sbin/arping -I $interface -c 3 -s $vip $gateway > /dev/null 2&>1";
my $ssh_stop_vip = "/sbin/ifconfig $interface:$key down";
GetOptions(
'command=s' => \$command,
'ssh_user=s' => \$ssh_user,
'orig_master_host=s' => \$orig_master_host,
'orig_master_ip=s' => \$orig_master_ip,
'orig_master_port=i' => \$orig_master_port,
'new_master_host=s' => \$new_master_host,
'new_master_ip=s' => \$new_master_ip,
'new_master_port=i' => \$new_master_port,
);
exit &main();
sub main {
print "\n\nIN SCRIPT TEST====$ssh_stop_vip==$ssh_start_vip===\n\n";
if ( $command eq "stop" || $command eq "stopssh" ) {
# $orig_master_host,$orig_master_ip,$orig_master_port are passed.
# If you manage master ip address at global catalog database,
# invalidate orig_master_ip here.
my $exit_code = 1;
eval {
print "Disabling the VIP on old master: $orig_master_host \n";
$exit_code = 0;
};
if ($@) {
warn "Got Error: $@\n";
exit $exit_code;
}
exit $exit_code;
}
elsif ( $command eq "start" ) {
# all arguments are passed.
# If you manage master ip address at global catalog database,
# activate new_master_ip here,
# You can also grant write access (create user, set read_only=0, etc) here.
my $exit_code = 10;
eval {
print "Enabling the VIP - $vip on the new master - $new_master_host \n";
&start_vip();
$exit_code = 0;
};
if ($@) {
warn $@;
exit $exit_code;
}
exit $exit_code;
}
elsif ( $command eq "status" ) {
print "Checking the Status of the script.. OK \n";
`ssh $ssh_user\@$orig_master_host \" $ssh_start_vip \"`;
exit 0;
}
else {
&usage();
exit 1;
}
}
# A simple system call that enable the VIP on the new master
sub start_vip() {
`ssh $ssh_user\@$new_master_host \" $ssh_start_vip \"`;
}
# A simple system call that disable the VIP on the old master
sub stop_vip() {
`ssh $ssh_user\@$orig_master_host \" $ssh_stop_vip \"`;
}
sub usage {
print
"Usage: master_ip_failover --command=start|stop|stopssh|status --orig_master_host=host --orig_master_ip=ip --orig_master_port=port --new_master_host=host --new_master_ip=ip --new_master_port=port\n";
}
[root@Centos7 ~]# chmod +x /usr/local/bin/master_ip_failover 

（5）实现master节点

#修改配置文件
[root@master ~]#cat /etc/my.cnf
[mysqld]
server-id=1         #指定固定id
log-bin=/data/mysql/mysql-bin    #开启二进制日志
skip_name_resolve=1             #禁止反向解析
datadir=/data/mysql
socket=/data/mysql/mysql.sock                                           
log-error=/data/mysql/mysql.log
pid-file=/data/mysql/mysql.pid
[client]
socket=/data/mysql/mysql.sock
#启动服务进入数据库
#查看当前二进制日志位置
mysql> show master logs;
+------------------+-----------+
| Log_name         | File_size |
+------------------+-----------+
| mysql-bin.000001 |       154 |
+------------------+-----------+
1 row in set (0.00 sec)
#创建复制所需账号，创建mha所需账号
mysql> grant replication slave on *.* to 'repluser'@'10.0.0.%' identified by '123456';
Query OK, 0 rows affected, 1 warning (0.04 sec)

mysql> grant all on *.* to mhauser@'10.0.0.%' identified by '123456';
Query OK, 0 rows affected, 1 warning (0.00 sec)
#配置VIP
[root@master ~]#ifconfig eth0:1 10.0.0.100/24
[root@master ~]#ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 00:0c:29:10:2e:9d brd ff:ff:ff:ff:ff:ff
    inet 10.0.0.68/24 brd 10.0.0.255 scope global noprefixroute eth0
       valid_lft forever preferred_lft forever
    inet 10.0.0.100/24 brd 10.0.0.255 scope global secondary eth0:1
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:fe10:2e9d/64 scope link 
       valid_lft forever preferred_lft forever

（6）实现slave1

#修改配置文件
[root@slave1 ~]#cat /etc/my.cnf
[mysqld]
server-id=2
log-bin=/data/mysql/mysql-bin   #开启二进制日志
datadir=/data/mysql
read_only
relay_log_purge=0              #不清除中继日志
skip_name_resolve=1             #禁止反向解析 
socket=/data/mysql/mysql.sock                                                                                   
log-error=/data/mysql/mysql.log
pid-file=/data/mysql/mysql.pid
[client]
socket=/data/mysql/mysql.sock
#进入数据库执行change master
mysql> CHANGE MASTER TO
    ->   MASTER_HOST='10.0.0.68',
    ->   MASTER_USER='repluser',
    ->   MASTER_PASSWORD='123456',
    ->   MASTER_PORT=3306,
    ->  MASTER_LOG_FILE='mysql-bin.000001', MASTER_LOG_POS=154;
Query OK, 0 rows affected, 2 warnings (0.04 sec)
mysql> start slave;

(7)实现slave2

#修改配置文件
[root@slave2 ~]#cat /etc/my.cnf 
[mysqld]
server-id=3
log-bin=/data/mysql/mysql-bin
read_only
relay_log_purge=0   
skip_name_resolve=1 
datadir=/data/mysql
socket=/data/mysql/mysql.sock                                                                     
log-error=/data/mysql/mysql.log
pid-file=/data/mysql/mysql.pid
[client]
socket=/data/mysql/mysql.sock
#进入数据库执行change master
mysql> CHANGE MASTER TO
    ->   MASTER_HOST='10.0.0.68',
    ->   MASTER_USER='repluser',
    ->   MASTER_PASSWORD='123456',
    ->   MASTER_PORT=3306,
    ->  MASTER_LOG_FILE='mysql-bin.000001', 
    ->  MASTER_LOG_POS=154;
Query OK, 0 rows affected, 2 warnings (0.05 sec)
mysql> start slave;

（8）检查MHA环境

[root@MHA-manager ~]# masterha_check_ssh --conf=/etc/mastermha/app1.cnf 
Sat Oct 17 11:03:38 2020 - [warning] Global configuration file /etc/masterha_default.cnf not found. Skipping.
Sat Oct 17 11:03:38 2020 - [info] Reading application default configuration from /etc/mastermha/app1.cnf..
Sat Oct 17 11:03:38 2020 - [info] Reading server configuration from /etc/mastermha/app1.cnf..
Sat Oct 17 11:03:38 2020 - [info] Starting SSH connection tests..
Sat Oct 17 11:03:39 2020 - [debug] 
Sat Oct 17 11:03:38 2020 - [debug]  Connecting via SSH from [email protected](10.0.0.68:22) to [email protected](10.0.0.58:22)..
Sat Oct 17 11:03:39 2020 - [debug]   ok.
Sat Oct 17 11:03:39 2020 - [debug]  Connecting via SSH from [email protected](10.0.0.68:22) to [email protected](10.0.0.48:22)..
Sat Oct 17 11:03:39 2020 - [debug]   ok.
Sat Oct 17 11:03:40 2020 - [debug] 
Sat Oct 17 11:03:38 2020 - [debug]  Connecting via SSH from [email protected](10.0.0.58:22) to [email protected](10.0.0.68:22)..
Warning: Permanently added '10.0.0.68' (ECDSA) to the list of known hosts.
Sat Oct 17 11:03:39 2020 - [debug]   ok.
Sat Oct 17 11:03:39 2020 - [debug]  Connecting via SSH from [email protected](10.0.0.58:22) to [email protected](10.0.0.48:22)..
Sat Oct 17 11:03:40 2020 - [debug]   ok.
Sat Oct 17 11:03:40 2020 - [debug] 
Sat Oct 17 11:03:39 2020 - [debug]  Connecting via SSH from [email protected](10.0.0.48:22) to [email protected](10.0.0.68:22)..
Warning: Permanently added '10.0.0.68' (ECDSA) to the list of known hosts.
Sat Oct 17 11:03:40 2020 - [debug]   ok.
Sat Oct 17 11:03:40 2020 - [debug]  Connecting via SSH from [email protected](10.0.0.48:22) to [email protected](10.0.0.58:22)..
Sat Oct 17 11:03:40 2020 - [debug]   ok.
Sat Oct 17 11:03:40 2020 - [info] All SSH connection tests passed successfully.
[root@MHA-manager ~]# masterha_check_repl --conf=/etc/mastermha/app1.cnf
Sat Oct 17 11:44:20 2020 - [warning] Global configuration file /etc/masterha_default.cnf not found. Skipping.
Sat Oct 17 11:44:20 2020 - [info] Reading application default configuration from /etc/mastermha/app1.cnf..
Sat Oct 17 11:44:20 2020 - [info] Reading server configuration from /etc/mastermha/app1.cnf..
Sat Oct 17 11:44:20 2020 - [info] MHA::MasterMonitor version 0.58.
Sat Oct 17 11:44:21 2020 - [info] GTID failover mode = 0
Sat Oct 17 11:44:21 2020 - [info] Dead Servers:
Sat Oct 17 11:44:21 2020 - [info] Alive Servers:
Sat Oct 17 11:44:21 2020 - [info]   10.0.0.68(10.0.0.68:3306)
Sat Oct 17 11:44:21 2020 - [info]   10.0.0.58(10.0.0.58:3306)
Sat Oct 17 11:44:21 2020 - [info]   10.0.0.48(10.0.0.48:3306)
Sat Oct 17 11:44:21 2020 - [info] Alive Slaves:
Sat Oct 17 11:44:21 2020 - [info]   10.0.0.58(10.0.0.58:3306)  Version=5.7.29-log (oldest major version between slaves) log-bin:enabled
Sat Oct 17 11:44:21 2020 - [info]     Replicating from 10.0.0.68(10.0.0.68:3306)
Sat Oct 17 11:44:21 2020 - [info]     Primary candidate for the new Master (candidate_master is set)
Sat Oct 17 11:44:21 2020 - [info]   10.0.0.48(10.0.0.48:3306)  Version=5.7.29-log (oldest major version between slaves) log-bin:enabled
Sat Oct 17 11:44:21 2020 - [info]     Replicating from 10.0.0.68(10.0.0.68:3306)
Sat Oct 17 11:44:21 2020 - [info] Current Alive Master: 10.0.0.68(10.0.0.68:3306)
Sat Oct 17 11:44:21 2020 - [info] Checking slave configurations..
Sat Oct 17 11:44:21 2020 - [info] Checking replication filtering settings..
Sat Oct 17 11:44:21 2020 - [info]  binlog_do_db= , binlog_ignore_db= 
Sat Oct 17 11:44:21 2020 - [info]  Replication filtering check ok.
Sat Oct 17 11:44:21 2020 - [info] GTID (with auto-pos) is not supported
Sat Oct 17 11:44:21 2020 - [info] Starting SSH connection tests..
Sat Oct 17 11:44:24 2020 - [info] All SSH connection tests passed successfully.
Sat Oct 17 11:44:24 2020 - [info] Checking MHA Node version..
Sat Oct 17 11:44:25 2020 - [info]  Version check ok.
Sat Oct 17 11:44:25 2020 - [info] Checking SSH publickey authentication settings on the current master..
Sat Oct 17 11:44:25 2020 - [info] HealthCheck: SSH to 10.0.0.68 is reachable.
Sat Oct 17 11:44:26 2020 - [info] Master MHA Node version is 0.58.
Sat Oct 17 11:44:26 2020 - [info] Checking recovery script configurations on 10.0.0.68(10.0.0.68:3306)..
Sat Oct 17 11:44:26 2020 - [info]   Executing command: save_binary_logs --command=test --start_pos=4 --binlog_dir=/data/mysql/ --output_file=/data/mastermha/app1//save_binary_logs_test --manager_version=0.58 --start_file=mysql-bin.000001 
Sat Oct 17 11:44:26 2020 - [info]   Connecting to [email protected](10.0.0.68:22).. 
  Creating /data/mastermha/app1 if not exists.. Creating directory /data/mastermha/app1.. done.
   ok.
  Checking output directory is accessible or not..
   ok.
  Binlog found at /data/mysql/, up to mysql-bin.000001
Sat Oct 17 11:44:26 2020 - [info] Binlog setting check done.
Sat Oct 17 11:44:26 2020 - [info] Checking SSH publickey authentication and checking recovery script configurations on all alive slave servers..
Sat Oct 17 11:44:26 2020 - [info]   Executing command : apply_diff_relay_logs --command=test --slave_user='mhauser' --slave_host=10.0.0.58 --slave_ip=10.0.0.58 --slave_port=3306 --workdir=/data/mastermha/app1/ --target_version=5.7.29-log --manager_version=0.58 --relay_log_info=/data/mysql/relay-log.info  --relay_dir=/data/mysql/  --slave_pass=xxx
Sat Oct 17 11:44:26 2020 - [info]   Connecting to [email protected](10.0.0.58:22).. 
Creating directory /data/mastermha/app1/.. done.
  Checking slave recovery environment settings..
    Opening /data/mysql/relay-log.info ... ok.
    Relay log found at /data/mysql, up to slave1-relay-bin.000002
    Temporary relay log file is /data/mysql/slave1-relay-bin.000002
    Checking if super_read_only is defined and turned on.. not present or turned off, ignoring.
    Testing mysql connection and privileges..
mysql: [Warning] Using a password on the command line interface can be insecure.
 done.
    Testing mysqlbinlog output.. done.
    Cleaning up test file(s).. done.
Sat Oct 17 11:44:27 2020 - [info]   Executing command : apply_diff_relay_logs --command=test --slave_user='mhauser' --slave_host=10.0.0.48 --slave_ip=10.0.0.48 --slave_port=3306 --workdir=/data/mastermha/app1/ --target_version=5.7.29-log --manager_version=0.58 --relay_log_info=/data/mysql/relay-log.info  --relay_dir=/data/mysql/  --slave_pass=xxx
Sat Oct 17 11:44:27 2020 - [info]   Connecting to [email protected](10.0.0.48:22).. 
Creating directory /data/mastermha/app1/.. done.
  Checking slave recovery environment settings..
    Opening /data/mysql/relay-log.info ... ok.
    Relay log found at /data/mysql, up to slave2-relay-bin.000002
    Temporary relay log file is /data/mysql/slave2-relay-bin.000002
    Checking if super_read_only is defined and turned on.. not present or turned off, ignoring.
    Testing mysql connection and privileges..
mysql: [Warning] Using a password on the command line interface can be insecure.
 done.
    Testing mysqlbinlog output.. done.
    Cleaning up test file(s).. done.
Sat Oct 17 11:44:27 2020 - [info] Slaves settings check done.
Sat Oct 17 11:44:27 2020 - [info] 
10.0.0.68(10.0.0.68:3306) (current master)
 +--10.0.0.58(10.0.0.58:3306)
 +--10.0.0.48(10.0.0.48:3306)

Sat Oct 17 11:44:27 2020 - [info] Checking replication health on 10.0.0.58..
Sat Oct 17 11:44:27 2020 - [info]  ok.
Sat Oct 17 11:44:27 2020 - [info] Checking replication health on 10.0.0.48..
Sat Oct 17 11:44:27 2020 - [info]  ok.
Sat Oct 17 11:44:27 2020 - [info] Checking master_ip_failover_script status:
Sat Oct 17 11:44:27 2020 - [info]   /usr/local/bin/master_ip_failover --command=status --ssh_user=root --orig_master_host=10.0.0.68 --orig_master_ip=10.0.0.68 --orig_master_port=3306 


IN SCRIPT TEST====/sbin/ifconfig eth0:1 down==/sbin/ifconfig eth0:1 10.0.0.100/24;/sbin/arping -I eth0 -c 3 -s 10.0.0.100/24 10.0.0.2 > /dev/null 2&>1===

Checking the Status of the script.. OK 
Sat Oct 17 11:44:28 2020 - [info]  OK.
Sat Oct 17 11:44:28 2020 - [warning] shutdown_script is not defined.
Sat Oct 17 11:44:28 2020 - [info] Got exit code 0 (Not master dead).

MySQL Replication Health is OK.

查看MHA状态

[root@MHA-manager ~]# masterha_check_status --conf=/etc/mastermha/app1.cnf
app1 is stopped(2:NOT_RUNNING).

（9）启动MHA

[root@MHA-manager ~]# nohup masterha_manager --conf=/etc/mastermha/app1.cnf &> /dev/null
[root@MHA-manager ~]# masterha_check_status --conf=/etc/mastermha/app1.cnf        #主服务器状态
app1 (pid:24874) is running(0:PING_OK), master:10.0.0.68

（10）模拟故障

[root@master ~]#systemctl stop mysqld.service      #停止主服务器
[root@MHA-manager ~]# nohup masterha_manager --conf=/etc/mastermha/app1.cnf &> /dev/null   #当主节点关闭后会自动退出mha








[root@MHA-manager ~]# 
[root@MHA-manager ~]# cat /data/mastermha/app1/manager.log     #查看日志看VIP漂移到哪个节点 新主节点为10.0.0.58
Sat Oct 17 12:38:44 2020 - [info]  Slave started.
Sat Oct 17 12:38:45 2020 - [info] End of log messages from 10.0.0.48.
Sat Oct 17 12:38:45 2020 - [info] -- Slave recovery on host 10.0.0.48(10.0.0.48:3306) succeeded.
Sat Oct 17 12:38:45 2020 - [info] All new slave servers recovered successfully.
Sat Oct 17 12:38:45 2020 - [info] 
Sat Oct 17 12:38:45 2020 - [info] * Phase 5: New master cleanup phase..
Sat Oct 17 12:38:45 2020 - [info] 
Sat Oct 17 12:38:45 2020 - [info] Resetting slave info on the new master..
Sat Oct 17 12:38:45 2020 - [info]  10.0.0.58: Resetting slave info succeeded.
Sat Oct 17 12:38:45 2020 - [info] Master failover to 10.0.0.58(10.0.0.58:3306) completed successfully.
Sat Oct 17 12:38:45 2020 - [info] 

----- Failover Report -----

app1: MySQL Master failover 10.0.0.68(10.0.0.68:3306) to 10.0.0.58(10.0.0.58:3306) succeeded

Master 10.0.0.68(10.0.0.68:3306) is down!

Check MHA Manager logs at MHA-manager:/data/mastermha/app1/manager.log for details.

Started automated(non-interactive) failover.
Invalidated master IP address on 10.0.0.68(10.0.0.68:3306)
The latest slave 10.0.0.58(10.0.0.58:3306) has all relay logs for recovery.
Selected 10.0.0.58(10.0.0.58:3306) as a new master.
10.0.0.58(10.0.0.58:3306): OK: Applying all logs succeeded.
10.0.0.58(10.0.0.58:3306): OK: Activated master IP address.
10.0.0.48(10.0.0.48:3306): This host has the latest relay log events.
Generating relay diff files from the latest slave succeeded.
10.0.0.48(10.0.0.48:3306): OK: Applying all logs succeeded. Slave started, replicating from 10.0.0.58(10.0.0.58:3306)
10.0.0.58(10.0.0.58:3306): Resetting slave info succeeded.
Master failover to 10.0.0.58(10.0.0.58:3306) completed successfully.
Sat Oct 17 12:38:45 2020 - [info] Sending mail..
#在10.0.0.58查看VIP已经漂移到本机
[root@slave1 ~]#ip a
1: lo:  mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: eth0:  mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 00:0c:29:02:7c:51 brd ff:ff:ff:ff:ff:ff
    inet 10.0.0.58/24 brd 10.0.0.255 scope global noprefixroute eth0
       valid_lft forever preferred_lft forever
    inet 10.0.0.100/24 brd 10.0.0.255 scope global secondary eth0:1
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:fe02:7c51/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever
#如果需要再次开启mha需要删除以下文件
[root@MHA-manager ~]# ls /data/mastermha/app1/app1.failover.complete 

收到邮件报警

4、mysql高可用性-Percona XtraDB Cluster(PXC 5.7）

（不支持centos8）

一、实验环境

pxc1:  10.0.0.27   centos7
pxc2:  10.0.0.37   centos7
pxc3:  10.0.0.47   centos7
pxc4:  10.0.0.57   centos7

二、实验步骤

（1）安装 Percona XtraDB Cluster 5.7

#配置清华大学yum源
[15:40:11 root@pxc1 ~]#cat /etc/yum.repos.d/pxc.repo 
[perconal]
name=percona_repo
baseurl = https://mirrors.tuna.tsinghua.edu.cn/percona/release/$releasever/RPMS/$basearch
enabled = 1
gpgcheck = 0
#将yum源拷贝到其他两个节点
[15:43:37 root@pxc1 ~]#scp /etc/yum.repos.d/pxc.repo 10.0.0.37:/etc/yum.repos.d/
[15:43:37 root@pxc1 ~]#scp /etc/yum.repos.d/pxc.repo 10.0.0.47:/etc/yum.repos.d/
#在三个节点都安装PXC 5.7
[15:43:37 root@pxc1 ~]#yum install Percona-XtraDB-Cluster-57 -y
[15:28:39 root@pxc2 ~]#yum install Percona-XtraDB-Cluster-57 -y
[root@pxc3 ~]# yum install Percona-XtraDB-Cluster-57 -y

（2）在各个节点上分别配置mysql及集群配置文件

/etc/my.cnf为主配置文件，当前版本中，其余的配置文件都放在/etc/percona-xtradb-cluster.conf.d目录里，包括mysqld.cnf，mysqld_safe.cnf，wsrep.cnf 三个文件

#修改PXC的配置文件
[16:11:47 root@pxc1 ~]#cat /etc/percona-xtradb-cluster.conf.d/wsrep.cnf
[mysqld]
# Path to Galera library
wsrep_provider=/usr/lib64/galera3/libgalera_smm.so

# Cluster connection URL contains IPs of nodes
#If no IP is found, this implies that a new cluster needs to be created,
#in order to do that you need to bootstrap this node
wsrep_cluster_address=gcomm://10.0.0.27,10.0.0.37,10.0.0.47          #三个节点的IP

# In order for Galera to work correctly binlog format should be ROW
binlog_format=ROW

# MyISAM storage engine has only experimental support
default_storage_engine=InnoDB

# Slave thread to use
wsrep_slave_threads= 8

wsrep_log_conflicts

# This changes how InnoDB autoincrement locks are managed and is a requirement for Galera
innodb_autoinc_lock_mode=2

# Node IP address
#wsrep_node_address=192.168.70.63
wsrep_node_address=10.0.0.27                                       #各个节点，指定自已的IP
# Cluster name
wsrep_cluster_name=pxc-magedu-cluster

#If wsrep_node_name is not specified,  then system hostname will be used
wsrep_node_name=pxc-cluster-node-1                                  #各个节点，指定自已节点名称

#pxc_strict_mode allowed values: DISABLED,PERMISSIVE,ENFORCING,MASTER
pxc_strict_mode=ENFORCING

# SST method
wsrep_sst_method=xtrabackup-v2

#Authentication for SST method
wsrep_sst_auth="gjz:123456"                                        #取消注释或者改为自己的密码

[16:09:38 root@pxc2 ~]#cat /etc/percona-xtradb-cluster.conf.d/wsrep.cnf
[mysqld]
# Path to Galera library
wsrep_provider=/usr/lib64/galera3/libgalera_smm.so

# Cluster connection URL contains IPs of nodes
#If no IP is found, this implies that a new cluster needs to be created,
#in order to do that you need to bootstrap this node
wsrep_cluster_address=gcomm://10.0.0.27,10.0.0.37,10.0.0.47

# In order for Galera to work correctly binlog format should be ROW
binlog_format=ROW

# MyISAM storage engine has only experimental support
default_storage_engine=InnoDB

# Slave thread to use
wsrep_slave_threads= 8

wsrep_log_conflicts

# This changes how InnoDB autoincrement locks are managed and is a requirement for Galera
innodb_autoinc_lock_mode=2

# Node IP address
#wsrep_node_address=192.168.70.63
wsrep_node_address=10.0.0.37
# Cluster name
wsrep_cluster_name=pxc-magedu-cluster

#If wsrep_node_name is not specified,  then system hostname will be used
wsrep_node_name=pxc-cluster-node-2

#pxc_strict_mode allowed values: DISABLED,PERMISSIVE,ENFORCING,MASTER
pxc_strict_mode=ENFORCING

# SST method
wsrep_sst_method=xtrabackup-v2

#Authentication for SST method
wsrep_sst_auth="gjz:123456"

[root@pxc3 ~]# cat /etc/percona-xtradb-cluster.conf.d/wsrep.cnf
[mysqld]
# Path to Galera library
wsrep_provider=/usr/lib64/galera3/libgalera_smm.so

# Cluster connection URL contains IPs of nodes
#If no IP is found, this implies that a new cluster needs to be created,
#in order to do that you need to bootstrap this node
wsrep_cluster_address=gcomm://10.0.0.27,10.0.0.37,10.0.0.47

# In order for Galera to work correctly binlog format should be ROW
binlog_format=ROW

# MyISAM storage engine has only experimental support
default_storage_engine=InnoDB

# Slave thread to use
wsrep_slave_threads= 8

wsrep_log_conflicts

# This changes how InnoDB autoincrement locks are managed and is a requirement for Galera
innodb_autoinc_lock_mode=2

# Node IP address
#wsrep_node_address=192.168.70.63
wsrep_node_address=10.0.0.47
# Cluster name
wsrep_cluster_name=pxc-magedu-cluster

#If wsrep_node_name is not specified,  then system hostname will be used
wsrep_node_name=pxc-cluster-node-3

#pxc_strict_mode allowed values: DISABLED,PERMISSIVE,ENFORCING,MASTER
pxc_strict_mode=ENFORCING

# SST method
wsrep_sst_method=xtrabackup-v2

#Authentication for SST method
wsrep_sst_auth="gjz:123456"

（3）启动第一个节点

[root@pxc3 ~]# systemctl start [email protected]
#查看root密码
[root@pxc3 ~]# grep "temporary password" /var/log/mysqld.log
2020-10-17T08:22:46.574773Z 1 [Note] A temporary password is generated for root@localhost: +?tLc;9/f7Pf
[root@pxc3 ~]# mysql -p'+?tLc;9/f7Pf'
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 12
Server version: 5.7.31-34-57-log

Copyright (c) 2009-2020 Percona LLC and/or its affiliates
Copyright (c) 2000, 2020, 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.

mysql> 
#修改root密码
mysql> alter user 'root'@'localhost' identified by 'magedu'
    -> ;
Query OK, 0 rows affected (0.00 sec)
#创建相关用户并授权
mysql> CREATE USER 'gjz'@'localhost' IDENTIFIED BY '123456';
Query OK, 0 rows affected (0.00 sec)

mysql> GRANT RELOAD, LOCK TABLES, PROCESS, REPLICATION CLIENT ON *.* TO 'gjz'@'localhost';
Query OK, 0 rows affected (0.00 sec)

（4）启动其他节点

[root@pxc1 ~]# systemctl start mysql
[16:15:27 root@pxc2 ~]#systemctl start mysql

（5）查看集群状态，验证集群是否成功

#在任意节点，查看集群状态，只要在第一个节点更改数据库root密码其他节点均可同步
[16:51:13 root@pxc2 ~]#mysql -uroot -pmagedu
mysql> show variables like 'wsrep_node_name';
+-----------------+--------------------+
| Variable_name   | Value              |
+-----------------+--------------------+
| wsrep_node_name | pxc-cluster-node-2 |
+-----------------+--------------------+
1 row in set (0.00 sec)
mysql> show variables like 'wsrep_node_address';
+--------------------+-----------+
| Variable_name      | Value     |
+--------------------+-----------+
| wsrep_node_address | 10.0.0.37 |
+--------------------+-----------+
1 row in set (0.00 sec)
#在任意节点查看数据库
mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| sys                |
+--------------------+
4 rows in set (0.00 sec)
#在任意节点创建数据库
#节点2创建数据库
mysql> create database testdb1;
Query OK, 1 row affected (0.00 sec)
#节点1查询
[root@pxc1 ~]# mysql -uroot -pmagedu
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 11
Server version: 5.7.31-34-57-log Percona XtraDB Cluster (GPL), Release rel34, Revision 7359e4f, WSREP version 31.45, wsrep_31.45

Copyright (c) 2009-2020 Percona LLC and/or its affiliates
Copyright (c) 2000, 2020, 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.

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| sys                |
| testdb1            |
+--------------------+
5 rows in set (0.00 sec)
#同时在三个节点创建数据库只有一个成功，无需担心复制冲突

（6）pxc集群加入新节点

#在PXC集群中再加一台新的主机PXC4：10.0.0.57
[17:25:11 root@pxc4 ~]#yum install Percona-XtraDB-Cluster-57 -y
[17:30:45 root@pxc4 ~]#cat /etc/percona-xtradb-cluster.conf.d/wsrep.cnf
[mysqld]
# Path to Galera library
wsrep_provider=/usr/lib64/galera3/libgalera_smm.so

# Cluster connection URL contains IPs of nodes
#If no IP is found, this implies that a new cluster needs to be created,
#in order to do that you need to bootstrap this node
wsrep_cluster_address=gcomm://10.0.0.27,10.0.0.37,10.0.0.47,10.0.0.57

# In order for Galera to work correctly binlog format should be ROW
binlog_format=ROW

# MyISAM storage engine has only experimental support
default_storage_engine=InnoDB

# Slave thread to use
wsrep_slave_threads= 8

wsrep_log_conflicts

# This changes how InnoDB autoincrement locks are managed and is a requirement for Galera
innodb_autoinc_lock_mode=2

# Node IP address
#wsrep_node_address=192.168.70.63
wsrep_node_address=10.0.0.57
# Cluster name
wsrep_cluster_name=pxc-magedu-cluster

#If wsrep_node_name is not specified,  then system hostname will be used
wsrep_node_name=pxc-cluster-node-4

#pxc_strict_mode allowed values: DISABLED,PERMISSIVE,ENFORCING,MASTER
pxc_strict_mode=ENFORCING

# SST method
wsrep_sst_method=xtrabackup-v2

#Authentication for SST method
wsrep_sst_auth="gjz:123456"
启动服务
[17:30:54 root@pxc4 ~]#systemctl start mysql
[17:32:08 root@pxc4 ~]#mysql -uroot -pmagedu
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 11
Server version: 5.7.31-34-57-log Percona XtraDB Cluster (GPL), Release rel34, Revision 7359e4f, WSREP version 31.45, wsrep_31.45

Copyright (c) 2009-2020 Percona LLC and/or its affiliates
Copyright (c) 2000, 2020, 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.

mysql> SHOW STATUS LIKE 'wsrep_cluster_size';
+--------------------+-------+
| Variable_name      | Value |
+--------------------+-------+
| wsrep_cluster_size | 4     |
+--------------------+-------+
1 row in set (0.01 sec)

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| sys                |
| testdb1            |
+--------------------+
5 rows in set (0.00 sec)

（7）在pxc集群中修复故障节点

#在任意节点停止服务
[17:43:45 root@pxc4 ~]#systemctl stop mysql.service 
#在其它任意节点查看wsrep_cluster_size变量少了一个节点
mysql> SHOW STATUS LIKE 'wsrep_cluster_size';
+--------------------+-------+
| Variable_name      | Value |
+--------------------+-------+
| wsrep_cluster_size | 3     |
+--------------------+-------+
1 row in set (0.01 sec)
mysql> create database testdb2;
Query OK, 1 row affected (0.01 sec)
#在其它任意节点可看到数据已同步
mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| sys                |
| testdb1            |
| testdb2            |
+--------------------+
6 rows in set (0.00 sec)
#将停止的节点启动，发现数据已经同步
[17:48:45 root@pxc4 ~]#systemctl start mysql
[17:48:45 root@pxc4 ~]#mysql -uroot -pmagedu
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 12
Server version: 5.7.31-34-57-log Percona XtraDB Cluster (GPL), Release rel34, Revision 7359e4f, WSREP version 31.45, wsrep_31.45

Copyright (c) 2009-2020 Percona LLC and/or its affiliates
Copyright (c) 2000, 2020, 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.

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| sys                |
| testdb1            |
| testdb2            |
+--------------------+
6 rows in set (0.00 sec)

mysql> 

5、通过 ansible 部署二进制 mysql 8

实验环境：
10.0.0.68  ansible主机
10.0.0.58
10.0.0.48

ansible管理首先要基于key验证，可通过以下脚本实现

#!/bin/bash

IPLIST="
10.0.0.68
10.0.0.58
10.0.0.48"

rpm -q sshpass &> /dev/null || yum -y install sshpass
[-f /root/.ssh/id_rsa] || ssh-keygen -f /root/.ssh/id_rsa -P ''
export SSHPASS=123456
for IP in $IPLIST;do
        sshpass -e ssh-copy-id $IP
done

[15:11:32 root@localhost ~]#vi mysql8.0-install.yml 

---
- hosts: mysql                                                                                                                                                                                                                                    
  remote_user: root
  gather_facts: no

  tasks:
    - name: add group mysql
      group: name=mysql state=present
    - name: add user mysql
      user: name=mysql state=present group=mysql
    - name: Install packeges
      yum: name=libaio,numactl-libs,libaio,ncurses-compat-libs
    - name: decompression
      unarchive: src=/root/mysql-8.0.21-linux-glibc2.12-x86_64.tar.xz dest=/usr/local
    - name: create symbolic link
      file: src=/usr/local/mysql-8.0.21-linux-glibc2.12-x86_64 dest=/usr/local/mysql state=link
    - name: modify path
      shell: echo 'PATH=/usr/local/mysql/bin/:$PATH' > /etc/profile.d/mysql.sh
    - name: modify path
      shell: source /etc/profile.d/mysql.sh
    - name: create my.cnf
      shell: echo -e '[mysqld]\nserver-id=1\nlog-bin\ndatadir=/data/mysql\nsocket=/data/mysql/mysql.sock\nlog-error=/data/mysql/mysql.log\npid-file=/data/mysql/mysql.pid\n[client]\nsocket=/data/mysql/mysql.sock'> /etc/my.cnf
    - name: install mysql
      shell: mysqld --initialize-insecure --user=mysql --datadir=/data/mysql
    - name: creat mysqld
      shell: cp /usr/local/mysql/support-files/mysql.server  /etc/init.d/mysqld
    - name: set auto run
      shell: chkconfig --add mysqld
    - name: start mysql
      service: name=mysqld state=started
    - name: modify password
      shell: mysql -e "alter user root@localhost identified by '123456'"