mysql多实例部署和传统主从
作者：互联网
mysql多实例部署和传统主从
1. 主从简介
在现代企业中，数据显得尤为重要，而存储数据的数据库选择又五花八门，但无论是何种数据库，均存在着一种隐患。
想几个问题：
- 用一台数据库存放数据，若此数据库服务器宕机了导致数据丢失怎么办？
- 业务量大了，数据多了，访问的人多了，一台数据库无法保证服务质量了怎么办？
1.1 主从作用
- 实时灾备，用于故障切换
- 读写分离，提供查询服务
- 备份，避免影响业务
1.2 主从形式
- 一主一从
- 主主复制
- 一主多从---扩展系统读取的性能，因为读是在从库读取的
- 多主一从---5.7开始支持
- 联级复制
2. 主从复制原理
主从复制步骤：
- 主库将所有的写操作记录到binlog日志中并生成一个log dump线程，将binlog日志传给从库的I/O线程
- 从库生成两个线程，一个I/O线程，一个SQL线程
- I/O线程去请求主库的binlog，并将得到的binlog日志写到relay log（中继日志） 文件中
- SQL线程，会读取relay log文件中的日志，并解析成具体操作，来实现主从的操作一致，达到最终数据一致的目的
3. 主从复制配置
主从复制配置步骤：
- 确保从数据库与主数据库里的数据一样
- 在主数据库里创建一个同步账号授权给从数据库使用
- 配置主数据库（修改配置文件）
- 配置从数据库（修改配置文件）
需求：
搭建两台MySQL服务器，一台作为主服务器，一台作为从服务器，主服务器进行写操作，从服务器进行读操作
环境说明：
| 数据库角色 | IP | 应用与系统版本 | 有无数据 |
|---|---|---|---|
| 主数据库 | 172.16.12.128 | centos8/redhat8 mysql-5.7 | 有数据 |
| 从数据库 | 172.16.12.129 | centos8/redhat8 mysql-5.7 | 无数据 |
3.1 mysql安装
分别在主从两台服务器上安装mysql-5.7版本，此处略过安装步骤，若有疑问请参考《mysql基础》与《mysql进阶》两篇文章。
3.2 mysql主从配置
3.2.1 确保从数据库与主数据库里的数据一样
为确保从数据库与主数据库里的数据一样，先全备主数据库并还原到从数据库中
//先查看主库有哪些库
[root@localhost ~]# mysql -uroot -pruntime123！ -e 'show databases;'
mysql: [Warning] Using a password on the command line interface can be insecure.
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| student |
| sys |
| teacher |
+--------------------+
//再查看从库有哪些库
[root@localhost ~]# mysql -uroot -pruntime123！ -e 'show databases;'
mysql: [Warning] Using a password on the command line interface can be insecure.
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| sys |
+--------------------+
//全备主库
mysql> FLUSH TABLES WITH READ LOCK;
Query OK, 0 rows affected (0.00 sec)
//备份主库并将备份文件传送到从库
[root@localhost ~]# mysqldump -uroot -pruntime123！ --all-databases > /opt/all-201808191200.sql
mysqldump: [Warning] Using a password on the command line interface can be insecure.
[root@localhost ~]# ls /opt/
all-201808191200.sql
[root@localhost ~]# scp /opt/all-201808191200.sql root@172.16.12.129:/opt/
root@172.16.12.129's password:
all-201808191200.sql 100% 786KB 10.6MB/s 00:00
//解除主库的锁表状态，直接退出交互式界面即可
mysql> quit
Bye
//在从库上恢复主库的备份并查看从库有哪些库，确保与主库一致
[root@localhost ~]# mysql -uroot -pruntime123！ < /opt/all-201808191200.sql
mysql: [Warning] Using a password on the command line interface can be insecure.
[root@localhost ~]# mysql -uroot -pruntime123！ -e 'show databases;'
mysql: [Warning] Using a password on the command line interface can be insecure.
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| student |
| sys |
| teacher |
+--------------------+
3.2.2 在主数据库里创建一个同步账号授权给从数据库使用
mysql> CREATE USER 'repl'@'172.16.12.129' IDENTIFIED BY 'repl123';
Query OK, 0 rows affected (0.00 sec)
mysql> GRANT REPLICATION SLAVE ON *.* TO 'repl'@'172.16.12.129';
Query OK, 0 rows affected (0.00 sec)
mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)
3.2.3 配置主数据库
[root@localhost ~]# vim /etc/my.cnf
//在[mysqld]这段的后面加上如下内容
[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
log-bin=mysql-bin //启用binlog日志
server-id=1 //数据库服务器唯一标识符，主库的server-id值必须比从库的大
symbolic-links=0
log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid
//重启mysql服务
[root@localhost ~]# systemctl restart mysqld
[root@localhost ~]# ss -antl
State Recv-Q Send-Q Local Address:Port Peer Address:Port
LISTEN 0 128 *:22 *:*
LISTEN 0 100 127.0.0.1:25 *:*
LISTEN 0 128 :::22 :::*
LISTEN 0 100 ::1:25 :::*
LISTEN 0 80 :::3306 :::*
//查看主库的状态
mysql> show master status;
+------------------+----------+--------------+------------------+-------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000001 | 154 | | | |
+------------------+----------+--------------+------------------+-------------------+
1 row in set (0.01 sec)
3.2.4 配置从数据库
[root@localhost ~]# vim /etc/my.cnf
//添加如下内容
[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
server-id=2 //设置从库的唯一标识符，从库的server-id值必须小于主库的该值
relay-log=mysql-relay-bin //启用中继日志relay-log
symbolic-links=0
log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid
//重启从库的mysql服务
[root@localhost ~]# systemctl restart mysqld
[root@localhost ~]# ss -antl
State Recv-Q Send-Q Local Address:Port Peer Address:Port
LISTEN 0 128 *:22 *:*
LISTEN 0 100 127.0.0.1:25 *:*
LISTEN 0 128 :::22 :::*
LISTEN 0 100 ::1:25 :::*
LISTEN 0 80 :::3306 :::*
//配置并启动主从复制
mysql> CHANGE MASTER TO
-> MASTER_HOST='172.16.12.128',
-> MASTER_USER='repl',
-> MASTER_PASSWORD='repl123',
-> MASTER_LOG_FILE='mysql-bin.000001',
-> MASTER_LOG_POS=154;
Query OK, 0 rows affected, 2 warnings (0.33 sec)
mysql> start slave;
Query OK, 0 rows affected (0.01 sec)
//查看从服务器状态
mysql> show slave status \G
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 172.16.12.128
Master_User: repl
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mysql-bin.000001
Read_Master_Log_Pos: 154
Relay_Log_File: mysql-relay-bin.000002
Relay_Log_Pos: 320
Relay_Master_Log_File: mysql-bin.000001
Slave_IO_Running: Yes //此处必须为Yes
Slave_SQL_Running: Yes //此处必须为Yes
Replicate_Do_DB:
Replicate_Ignore_DB:
3.2.5 测试验证
在主服务器的student库的bj2表中插入数据：
mysql> select * from bj2;
Empty set (0.00 sec)
mysql> insert into bj2 values (1,'sean',20),(2,'tom',23),(3,'jerry',30);
Query OK, 3 rows affected (0.00 sec)
Records: 3 Duplicates: 0 Warnings: 0
mysql> select * from bj2;
+----+-------+------+
| id | name | age |
+----+-------+------+
| 1 | sean | 20 |
| 2 | tom | 23 |
| 3 | jerry | 30 |
+----+-------+------+
3 rows in set (0.00 sec)
在从数据库中查看数据是否同步：
mysql> use student;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed
mysql> select * from bj2;
+----+-------+------+
| id | name | age |
+----+-------+------+
| 1 | sean | 20 |
| 2 | tom | 23 |
| 3 | jerry | 30 |
+----+-------+------+
3 rows in set (0.00 sec)
mysql多实例部署
用户和组并解压下本地配置程序至/usr/
//创建用户和组
[root@localhost src]# groupadd -r mysql
[root@localhost src]# useradd -M -s /sbin/nologin -g mysql mysql
//解压软件至/usr/local/
[root@localhost src]# ls
debug kernels mysql-5.7.22-linux-glibc2.12-x86_64.tar.gz
[root@localhost src]# tar xf mysql-5.7.22-linux-glibc2.12-x86_64.tar.gz -C /usr/local/
[root@localhost ~]# ls /usr/local/
bin games lib libexec sbin src
etc include lib64 mysql-5.7.22-linux-glibc2.12-x86_64 share
[root@localhost ~]# cd /usr/local/
[root@localhost local]# ln -sv mysql-5.7.22-linux-glibc2.12-x86_64/ mysql
‘mysql’ -> ‘mysql-5.7.22-linux-glibc2.12-x86_64/’
[root@localhost local]# ll
total 0
drwxr-xr-x. 2 root root 6 Mar 10 2016 bin
drwxr-xr-x. 2 root root 6 Mar 10 2016 etc
drwxr-xr-x. 2 root root 6 Mar 10 2016 games
drwxr-xr-x. 2 root root 6 Mar 10 2016 include
drwxr-xr-x. 2 root root 6 Mar 10 2016 lib
drwxr-xr-x. 2 root root 6 Mar 10 2016 lib64
drwxr-xr-x. 2 root root 6 Mar 10 2016 libexec
lrwxrwxrwx 1 root root 36 Aug 14 16:00 mysql -> mysql-5.7.22-linux-glibc2.12-x86_64/
drwxr-xr-x 9 root root 129 Aug 14 00:16 mysql-5.7.22-linux-glibc2.12-x86_64
drwxr-xr-x. 2 root root 6 Mar 10 2016 sbin
drwxr-xr-x. 5 root root 49 Jun 13 19:03 share
drwxr-xr-x. 2 root root 6 Mar 10 2016 src
//修改目录/usr/local/mysql的属主属组
[root@localhost ~]# chown -R mysql.mysql /usr/local/mysql
[root@localhost ~]# ll /usr/local/mysql -d
lrwxrwxrwx 1 mysql mysql 36 Aug 14 16:00 /usr/local/mysql -> mysql-5.7.22-linux-glibc2.12-x86_64/
//配置环境变量
[root@localhost ~]# echo 'export PATH=/usr/local/mysql/bin:$PATH' > /etc/profile.d/mysql.sh
[root@localhost ~]# . /etc/profile.d/mysql.sh
[root@localhost ~]# echo $PATH
/usr/local/mysql/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/root/bin
创建各个数据存放的目录
[root@localhost ~]# mkdir -p /opt/data/{3306,3307,3308}
[root@localhost ~]# chown -R mysql.mysql /opt/data/
[root@localhost ~]# ll /opt/data/
总用量 0
drwxr-xr-x 2 mysql mysql 6 5月 9 21:24 3306
drwxr-xr-x 2 mysql mysql 6 5月 9 21:24 3307
drwxr-xr-x 2 mysql mysql 6 5月 9 21:24 3308
[root@localhost ~]# tree /opt/data/
/opt/data/
├── 3306
├── 3307
└── 3308
3 directories, 0 files
初始化各实例
//初始化3306实例
[root@localhost ~]# mysqld --initialize --datadir=/opt/data/3306 --user=mysql
2019-05-10T01:43:33.987463Z 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).
2019-05-10T01:43:34.565759Z 0 [Warning] InnoDB: New log files created, LSN=45790
2019-05-10T01:43:34.733540Z 0 [Warning] InnoDB: Creating foreign key constraint system tables.
2019-05-10T01:43:34.808595Z 0 [Warning] No existing UUID has been found, so we assume that this is the first time that this server has been started. Generating a new UUID: 061b480e-72c5-11e9-ae30-000c29c0ed3b.
2019-05-10T01:43:34.810131Z 0 [Warning] Gtid table is not ready to be used. Table 'mysql.gtid_executed' cannot be opened.
2019-05-10T01:43:34.837499Z 1 [Note] A temporary password is generated for root@localhost: Y=lJV79Rkx,d
[root@localhost ~]# echo 'Y=lJV79Rkx,d' > 3306_pass
//初始化3307实例
[root@localhost ~]# mysqld --initialize --datadir=/opt/data/3307 --user=mysql
2019-05-10T01:45:41.206120Z 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).
2019-05-10T01:45:42.082891Z 0 [Warning] InnoDB: New log files created, LSN=45790
2019-05-10T01:45:42.258639Z 0 [Warning] InnoDB: Creating foreign key constraint system tables.
2019-05-10T01:45:42.352269Z 0 [Warning] No existing UUID has been found, so we assume that this is the first time that this server has been started. Generating a new UUID: 5220e72b-72c5-11e9-b195-000c29c0ed3b.
2019-05-10T01:45:42.353339Z 0 [Warning] Gtid table is not ready to be used. Table 'mysql.gtid_executed' cannot be opened.
2019-05-10T01:45:42.354494Z 1 [Note] A temporary password is generated for root@localhost: bpG+yqeGN8G:
[root@localhost ~]# echo 'bpG+yqeGN8G:' > 3307_pass
//3308
[root@localhost ~]# mysqld --initialize --datadir=/opt/data/3308 --user=mysql
2019-05-10T01:46:52.707755Z 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).
2019-05-10T01:46:53.546346Z 0 [Warning] InnoDB: New log files created, LSN=45790
2019-05-10T01:46:53.732779Z 0 [Warning] InnoDB: Creating foreign key constraint system tables.
2019-05-10T01:46:53.810767Z 0 [Warning] No existing UUID has been found, so we assume that this is the first time that this server has been started. Generating a new UUID: 7cb89aad-72c5-11e9-b5a1-000c29c0ed3b.
2019-05-10T01:46:53.813509Z 0 [Warning] Gtid table is not ready to be used. Table 'mysql.gtid_executed' cannot be opened.
2019-05-10T01:46:53.815051Z 1 [Note] A temporary password is generated for root@localhost: wior7yf:1Awu
[root@localhost ~]# echo 'wior7yf:1Awu' > 3308_pass
安装perl
[root@localhost ~]# yum -y install perl
配置配置文件/etc/my.cnf
[root@localhost ~]# vim /etc/my.cnf
[mysqld_multi]
mysqld = /usr/local/mysql/bin/mysqld_safe
mysqladmin = /usr/local/mysql/bin/mysqladmin
[mysqld3306]
datadir = /opt/data/3306
port = 3306
socket = /tmp/mysql3306.sock
pid-file = /opt/data/3306/mysql_3306.pid
log-error=/var/log/3306.log
[mysqld3307]
datadir = /opt/data/3307
port = 3307
socket = /tmp/mysql3307.sock
pid-file = /opt/data/3307/mysql_3307.pid
log-error=/var/log/3307.log
[mysqld3308]
datadir = /opt/data/3308
port = 3308
socket = /tmp/mysql3308.sock
pid-file = /opt/data/3308/mysql_3308.pid
log-error=/var/log/3308.log
启动各实例
[root@localhost ~]# mysqld_multi start 3306
[root@localhost ~]# mysqld_multi start 3307
[root@localhost ~]# mysqld_multi start 3308
[root@localhost ~]# ss -antl
State Recv-Q Send-Q Local Address:Port Peer Address:Port
LISTEN 0 128 *:22 *:*
LISTEN 0 100 127.0.0.1:25 *:*
LISTEN 0 80 :::3307 :::*
LISTEN 0 80 :::3308 :::*
LISTEN 0 128 :::22 :::*
LISTEN 0 100 ::1:25 :::*
LISTEN 0 80 :::3306 :::*
初始化密码
[root@localhost ~]# ls
3306_pass 3307_pass 3308_pass anaconda-ks.cfg
[root@localhost ~]# cat 3306_pass
Y=lJV79Rkx,d
[root@localhost ~]# mysql -uroot -p'Y=lJV79Rkx,d' -S /tmp/mysql3306.sock
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 3
Server version: 5.7.22
Copyright (c) 2000, 2018, 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> set password = password('wangqing123!');
Query OK, 0 rows affected, 1 warning (0.01 sec)
mysql> quit
Bye
[root@localhost ~]# cat 3307_pass
bpG+yqeGN8G:
[root@localhost ~]# mysql -uroot -p'bpG+yqeGN8G:' -S /tmp/mysql3307.sock -e 'set password = password("wangqing123!");' --connect-expired-password
mysql: [Warning] Using a password on the command line interface can be insecure.
[root@localhost ~]# cat 3308_pass
wior7yf:1Awu
[root@localhost ~]# mysql -uroot -p'wior7yf:1Awu' -S /tmp/mysql3308.sock -e 'set password = password("wangqing123!");' --connect-expired-password
mysql: [Warning] Using a password on the command line interface can be insecure.
标签：log,Warning,实例,mysqld,mysql,root,主从,localhost 来源： https://www.cnblogs.com/wg123/p/16441256.html