实战-Mysql主从复制

前言：

Mysql内建的复制功能是构建大型高性能应用程序的基础。由于目前mysql的高可用性架构MMM和MHA均建立在复制的基础之上，本文就mysql主从复制进行实战描述，希望对读者提供帮助。之前

服务器规划：

主库：192.168.2.153

备库：192.168.2.154

mysql版本使用5.6.26脚本编译安装，并指定数据目录。

主从复制：

1.创建复制账号：

主库：
mysql> grant replication slave on *.* to repl@'192.168.2.%' identified by 'slave';
备库：
mysql> grant replication slave on *.* to repl@'192.168.2.%' identified by 'slave';

2.配置主库和备库：

修改my.cnf：

            主库:
            log_bin = mysql-bin
            server_id= 153
            备库：
            log_bin = mysql-bin
            server_id = 154
            relay_log = /mvtech/mysql/log/mysql-relay-bin
            log_slave_updates = 1
            read_only = 1(不知道应用场合 暂时不添加)

3.启动复制

        备库：
            CHANGE MASTER TO MASTER_HOST='192.168.2.153',
            MASTER_USER='repl',
            MASTER_PASSWORD='slave',
            MASTER_LOG_FILE='mysql-bin.000006',
            MASTER_LOG_POS=0;
        查看状态：show slave status\G
            Slave_IO_Running: No
                        Slave_SQL_Running: No

        启动备库
            start slave
        查看备库状态：show slave status\G
            Slave_IO_Running: Yes
                        Slave_SQL_Running: Yes
        查看备库线程：
        show processlist\G

4.附主库和备库的my.cnf

主库：

[mysqld]
sql_mode=NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES
server-id = 153
skip-name-resolve
#skip-networking
back_log = 500
max_connections = 1000
max_connect_errors = 600
open_files_limit = 65535
table_open_cache = 384
max_allowed_packet = 4M
binlog_cache_size = 1M
max_heap_table_size = 8M
tmp_table_size = 16M
read_buffer_size = 2M
read_rnd_buffer_size = 16M
sort_buffer_size = 16M
join_buffer_size = 8M
thread_cache_size = 8
query_cache_size = 8M
query_cache_limit = 2M
key_buffer_size = 512M
ft_min_word_len = 4
transaction_isolation = REPEATABLE-READ
log_bin = mysql-bin
binlog_format = mixed
expire_logs_days = 30
log_error = /mvtech/mysql/log/mysql-error.log
slow_query_log = 1
long_query_time = 6
performance_schema = 0
explicit_defaults_for_timestamp
#lower_case_table_names = 1
skip-external-locking
default-storage-engine = InnoDB
innodb_file_per_table = 1
innodb_open_files = 500
innodb_buffer_pool_size = 64M
innodb_write_io_threads = 4
innodb_read_io_threads = 4
innodb_thread_concurrency = 8
innodb_purge_threads = 1
innodb_flush_log_at_trx_commit = 2
innodb_log_buffer_size = 2M
innodb_log_file_size = 32M
innodb_log_files_in_group = 3
innodb_max_dirty_pages_pct = 90
innodb_lock_wait_timeout = 120
bulk_insert_buffer_size = 8M
myisam_sort_buffer_size = 64M
myisam_max_sort_file_size = 10G
myisam_repair_threads = 1
interactive_timeout = 28800
wait_timeout = 28800
[mysqldump]
quick
max_allowed_packet = 16M
[myisamchk]
key_buffer_size = 8M
sort_buffer_size = 8M
read_buffer = 4M
write_buffer = 4M

备库：

[mysqld]
sql_mode=NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES
server-id = 154
skip-name-resolve
#skip-networking
back_log = 500
max_connections = 1000
max_connect_errors = 600
open_files_limit = 65535
table_open_cache = 384
max_allowed_packet = 4M
binlog_cache_size = 1M
max_heap_table_size = 8M
tmp_table_size = 16M
read_buffer_size = 2M
read_rnd_buffer_size = 16M
sort_buffer_size = 16M
join_buffer_size = 8M
thread_cache_size = 8
query_cache_size = 8M
query_cache_limit = 2M
key_buffer_size = 512M
ft_min_word_len = 4
transaction_isolation = REPEATABLE-READ
log_bin = mysql-bin
#slave add
relay_log = /mvtech/mysql/log/mysql-relay-bin
read_only = 1
log_slave_updates = 1
skip_slave_start
#slave add
binlog_format = mixed
expire_logs_days = 30
log_error = /mvtech/mysql/log/mysql-error.log
slow_query_log = 1
long_query_time = 6
performance_schema = 0
explicit_defaults_for_timestamp
#lower_case_table_names = 1
skip-external-locking
default-storage-engine = InnoDB
innodb_file_per_table = 1
innodb_open_files = 500
innodb_buffer_pool_size = 64M
innodb_write_io_threads = 4
innodb_read_io_threads = 4
innodb_thread_concurrency = 8
innodb_purge_threads = 1
innodb_flush_log_at_trx_commit = 2
innodb_log_buffer_size = 2M
innodb_log_file_size = 32M
innodb_log_files_in_group = 3
innodb_max_dirty_pages_pct = 90
innodb_lock_wait_timeout = 120
bulk_insert_buffer_size = 8M
myisam_sort_buffer_size = 64M
myisam_max_sort_file_size = 10G
myisam_repair_threads = 1
interactive_timeout = 28800
wait_timeout = 28800
[mysqldump]
quick
max_allowed_packet = 16M
[myisamchk]
key_buffer_size = 8M
sort_buffer_size = 8M
read_buffer = 4M
write_buffer = 4M

5.测试主从复制

在主库中创建新库，备库也有新库产生，往主库中导入大量数据时可通过show processlist \G 查看执行操作，

6.mysql手工切换主从

#主库： show slave hosts; #备库： #查看状态 mysql> show slave status\G #关闭IO线程 mysql> stop slave IO_THREAD; mysql> stop slave; mysql> reset master; mysql> show slave status\G mysql> reset slave all; #此时丛库已恢复至单机状态。 mysql> show binary logs; #主库操作： CHANGE MASTER TO MASTER_HOST='192.168.2.154', MASTER_USER='repl', MASTER_PASSWORD='slave', MASTER_LOG_FILE='mysql-bin.000003', MASTER_LOG_POS=120;

手动切换主从复制完毕。

注：mysql user库中有空的用户建议删掉，因为有时切换时会出现不使用密码即可登录的现象。将空用户删掉后重启mysql即可