MySQL 的半同步是通过加载 Google 为 MySQL 提供的半同步插件 semisync_master.so 和 semisync_slave.so 来实现的。其中前者是 Master 上需要安装的插件,后者是 Slave 上需要安装的插件。 MySQL 的插件位置默认存放在 $basedir/lib/plugin
MHA (Master High Availability) 目前是 MySQL 高可用相对成熟的解决方案之一,它由日本DeNA公司 youshimaton(现就职于Facebook公司)开发,是一套优秀的故障切换、主从提升的高可用软件。在 MySQL 故障切换过程中,MHA能做到0~30秒之内自动完成数据库的故障切换操作,并且在进行故障切换的过程中,MHA能最大程度上保证数据库的一致性,以达到真正意义上的高可用。基于标准的MySQL复制(异步/半同步)。
# 初始化mariadb (mariadb一定要成功启动才可以执行这一步,否则会报错)
[root@localhost ~]# mysql_secure_installation
NOTE: RUNNING ALL PARTS OF THIS SCRIPT IS RECOMMENDED FOR ALL MariaDB
SERVERS IN PRODUCTION USE! PLEASE READ EACH STEP CAREFULLY!
In order to log into MariaDB to secure it, we'll need the current
password for the root user. If you've just installed MariaDB, and
haven't set the root password yet, you should just press enter here.
Enter current password for root (enter for none):
OK, successfully used password, moving on...
Setting the root password or using the unix_socket ensures that nobody
can log into the MariaDB root user without the proper authorisation.
You already have your root account protected, so you can safely answer 'n'.
Switch to unix_socket authentication [Y/n] Y
Enabled successfully!
Reloading privilege tables..
... Success!
You already have your root account protected, so you can safely answer 'n'.
Change the root password? [Y/n] Y
New password:
Re-enter new password:
Password updated successfully!
Reloading privilege tables..
... Success!
By default, a MariaDB installation has an anonymous user, allowing anyone
to log into MariaDB without having to have a user account created for
them. This is intended only for testing, and to make the installation
go a bit smoother. You should remove them before moving into a
production environment.
Remove anonymous users? [Y/n] Y
... Success!
Normally, root should only be allowed to connect from 'localhost'. This
ensures that someone cannot guess at the root password from the network.
Disallow root login remotely? [Y/n] n
... skipping.
By default, MariaDB comes with a database named 'test' that anyone can
access. This is also intended only for testing, and should be removed
before moving into a production environment.
Remove test database and access to it? [Y/n] Y
- Dropping test database...
... Success!
- Removing privileges on test database...
... Success!
Reloading the privilege tables will ensure that all changes made so far
will take effect immediately.
Reload privilege tables now? [Y/n] Y
... Success!
Cleaning up...
All done! If you've completed all of the above steps, your MariaDB
installation should now be secure.
Thanks for using MariaDB!