一、环境。 1、服务器：准备 4 台虚拟机。 2、操作系统： windows2008R2SP2 或者以上版本。 3、数据库： Sqlserver2012 。 二、操作系统安装及设置。 4 、在 4 台虚拟机上均装上操作系统 windows2008R2, 并分别设置计算机名为 :DomainServer 、 DB1 、 DB2
一、环境。
1、服务器：准备4台虚拟机。
2、操作系统：windows2008 R2 SP2或者以上版本。
3、数据库：Sqlserver 2012。
二、操作系统安装及设置。
4、在4台虚拟机上均装上操作系统windows 2008 R2,并分别设置计算机名为:DomainServer、DB1、DB2、DB3，分别设置IP为192.168.100.20、192.168.100.21、192.168.100.22、192.168.100.23。
5、在DB1、DB2、DB3上开启功能.NET3.5 SP1。
6、在DB1、DB2、DB3上安装Sqlserver2012。
7、在DomainServer服务器上建立域服务alwayson.com、并将DB1、DB2、DB3的DNS设置为192.168.100.20，然后加如域alwayson.com。
三、windows2008故障转移群集部署。
8、以alwayson.com\administrator域帐户登录DB1、DB2、DB3，并添加故障转移集群功能。
9、在DB1、DB2、DB3中任一台机上创建群集，并将DB1、DB2、DB3台服务器添加进去、群集名称为alwaysoncluster,群集IP为192.168.100.25,仲裁配置为“多数节点”。
四、alwayson部署。
10、关闭DB1、DB2、DB3的防火墙或者在防火墙规则中添加例外端口1433、5022。
11、分别打开DB1、DB2、DB3的“SQL Server 配置管理器”，在左侧的“SQL Server 服务”列表中找到默认的实例,并开启alwayson功能。
12、将Sqlserver服务的登录帐户更改为域帐户alwayson.com\administrator，并重启sqlserver服务。
13、分别使用数据库管理工具连接DB1、DB2、DB3的数据库，并创建sqlserver的域登录帐户alwayson.com\administrator，并赋予sysadmin角色。
14、在DB1、DB2、DB3的分别建立目录D:\SQLDATA用于存放sql数据库文件，在局域网内建立一个可读写共享目录，该共享目录用于存放快照文件。要消除单点故障，可考虑将该共享存放在DFS共享上。
15、在DB1上新建数据库，数据文件存放在上面的新建文件夹D:\sqldata下，并做一次完整备份，要使用alwayson的数据库必须先完备一次。
16、以域管理员帐户登录DB1、打开“Sql Server Management Studio”，展开“alwayson高可用性”，并新建alwayson可用性组，命名为alwayson。
17、选择刚刚完备过的数据库。
18、在指定副本中添加DB1、DB2和DB3，其中DB1为主，DB2和DB3为辅；DB1和DB2为自动故障转移，同步提交，DB3不是自动故障转移且为异步提交，DB1和DB2、DB3均为可读辅助副本。
19、选择数据同步中选择完整，并填入用于存放快照的共享文件夹位置，然后直接下一步直至alwayson部署完成。
20、添加侦听器，在添加可用性组的地方选择添加侦听器，名称为alwaysonconn,IP为192.168.100.25，端口为1433，此连接用于程序连接，此伪IP信息始终在主数据库服务器上，若使用集群伪IP192.168.100.24会出现该IP不在主数据库服务器上的错误。
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