MongoDB--集群

为什么需要集群

• 为了让数据安全
• 高（24* 7）数据可用性
• 灾难恢复
• 无停机维护（如备份，索引重建，压实）
• 读缩放（额外的副本读取）
• 副本集对应用程序是透明

设置集群

准备工作

在MongoDB的集群是需要奇数个节点才能正常的运行，我们这里设置一个最小的节点的集群：1个主节点和2个从节点

1. 分别建立三个文件夹来存放MongoDB的三个节点的文件
   
   

   

2. 设置mongod.cfg文件

    systemLog:
    	destination: file
    	path: D:\Program Files\MongoDB\Server\3.0\0\log\mongod.log
    storage:
    	dbPath: D:\Program Files\MongoDB\Server\3.0\0\blogDB
    #网络
    net:
    	port: 27017
    #    bindIp: 127.0.0.1,192.168.1.106 #默认是全部IP
    #授权
    security:
    	authorization: disabled
    #    keyFile: D:\Program Files\MongoDB\Server\3.0\rsKey #用于集群的验证，建议使用ssl，我为了简单，rsKey只是一个普通的文本
    #集群
    replication:
    	replSetName: rs0 #集群名
   

三个节点的配置除了端口和路径需要改改，其他基本一致，我的三个节点的端口分别为：27017,27018,27019

启动集群

分别启动三个MongoDB实例，具体怎么启动，请参考我的MongoDB——基础入门

配置集群

C:\Users\Tengit>mongo
MongoDB shell version: 3.0.6
connecting to: test
> rs.initiate()
{
		"info2" : "no configuration explicitly specified -- making one",
		"me" : "tengit-2:27017",
		"ok" : 1
}
rs0:PRIMARY> rs.add("tengit-2:27018")
{ "ok" : 1 }
rs0:PRIMARY> rs.add("tengit-2:27019")
{ "ok" : 1 }
rs0:PRIMARY> rs.status()
{
		"set" : "rs0",
		"date" : ISODate("2015-10-14T02:51:00.788Z"),
		"myState" : 1,
		"members" : [
				{
						"_id" : 0,
						"name" : "tengit-2:27017",
						"health" : 1,
						"state" : 1,
						"stateStr" : "PRIMARY",
						"uptime" : 122,
						"optime" : Timestamp(1444791053, 1),
						"optimeDate" : ISODate("2015-10-14T02:50:53Z"),
						"electionTime" : Timestamp(1444790978, 2),
						"electionDate" : ISODate("2015-10-14T02:49:38Z"),
						"configVersion" : 3,
						"self" : true
				},
				{
						"_id" : 1,
						"name" : "tengit-2:27018",
						"health" : 1,
						"state" : 2,
						"stateStr" : "SECONDARY",
						"uptime" : 32,
						"optime" : Timestamp(1444791053, 1),
						"optimeDate" : ISODate("2015-10-14T02:50:53Z"),
						"lastHeartbeat" : ISODate("2015-10-14T02:50:59.873Z"),
						"lastHeartbeatRecv" : ISODate("2015-10-14T02:51:00.118Z"
),
						"pingMs" : 0,
						"syncingTo" : "tengit-2:27017",
						"configVersion" : 3
				},
				{
						"_id" : 2,
						"name" : "tengit-2:27019",
						"health" : 1,
						"state" : 5,
						"stateStr" : "STARTUP2",
						"uptime" : 6,
						"optime" : Timestamp(0, 0),
						"optimeDate" : ISODate("1970-01-01T00:00:00Z"),
						"lastHeartbeat" : ISODate("2015-10-14T02:50:59.871Z"),
						"lastHeartbeatRecv" : ISODate("2015-10-14T02:51:00.138Z"
),
						"pingMs" : 0,
						"configVersion" : 3
				}
		],
		"ok" : 1
}
rs0:PRIMARY> rs.status()
{
		"set" : "rs0",
		"date" : ISODate("2015-10-14T02:51:50.492Z"),
		"myState" : 1,
		"members" : [
				{
						"_id" : 0,
						"name" : "tengit-2:27017",
						"health" : 1,
						"state" : 1,
						"stateStr" : "PRIMARY",
						"uptime" : 172,
						"optime" : Timestamp(1444791053, 1),
						"optimeDate" : ISODate("2015-10-14T02:50:53Z"),
						"electionTime" : Timestamp(1444790978, 2),
						"electionDate" : ISODate("2015-10-14T02:49:38Z"),
						"configVersion" : 3,
						"self" : true
				},
				{
						"_id" : 1,
						"name" : "tengit-2:27018",
						"health" : 1,
						"state" : 2,
						"stateStr" : "SECONDARY",
						"uptime" : 82,
						"optime" : Timestamp(1444791053, 1),
						"optimeDate" : ISODate("2015-10-14T02:50:53Z"),
						"lastHeartbeat" : ISODate("2015-10-14T02:51:49.886Z"),
						"lastHeartbeatRecv" : ISODate("2015-10-14T02:51:50.125Z"
),
						"pingMs" : 0,
						"syncingTo" : "tengit-2:27017",
						"configVersion" : 3
				},
				{
						"_id" : 2,
						"name" : "tengit-2:27019",
						"health" : 1,
						"state" : 2,
						"stateStr" : "SECONDARY",
						"uptime" : 56,
						"optime" : Timestamp(1444791053, 1),
						"optimeDate" : ISODate("2015-10-14T02:50:53Z"),
						"lastHeartbeat" : ISODate("2015-10-14T02:51:49.886Z"),
						"lastHeartbeatRecv" : ISODate("2015-10-14T02:51:50.150Z"
),
						"pingMs" : 0,
						"configVersion" : 3
				}
		],
		"ok" : 1
}
rs0:PRIMARY>

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