MongoDB 副本集主從切換方法

一、方法一rs.setpDown()

將Primary節點降級為Secondary節點

myapp:PRIMARY> rs.stepDown()

這個命令會讓primary降級為Secondary節點，並維持60s，如果這段時間內沒有新的primary被選舉出來，這個節點可以要求重新進行選舉。

也可手動指定時間

myapp:PRIMARY> rs.stepDown(30)

在執行完該命令后，原Secondary node3:27017升級為Primary。

二、方法二優先級設置

思路:
1.為了保證數據的一致性，必須先關閉應用的寫服務。
2.提升要升級為Primary節點的Secondary節點的優先級。

操作如下:

點擊(此處)折疊或打開

 arps:PRIMARY> config=rs.conf()                //查看當前配置，存入config變量中。
 arps:PRIMARY> config.members[2].priority = 3  //修改config變量，第三組成員的優先級為3.
 arps:PRIMARY> rs.reconfig(config)             //配置生效
 ......
 ......
 2017-12-22T15:19:56.596+0800 I NETWORK trying reconnect to 127.0.0.1:27017 (127.0.0.1) failed
 2017-12-22T15:19:56.597+0800 I NETWORK reconnect 127.0.0.1:27017 (127.0.0.1) ok

 arps:SECONDARY> rs.conf()                    //查看當前配置
 {
         "_id" : "arps",
         "version" : 4,
         "members" : [
                 {
                         "_id" : 0,
                         "host" : "172.17.4.37:27017",
                         "arbiterOnly" : false,
                         "buildIndexes" : true,
                         "hidden" : false,
                         "priority" : 1,
                         "tags" : {

                         },
                         "slaveDelay" : 0,
                         "votes" : 1
                 },
                 {
                         "_id" : 1,
                         "host" : "172.17.4.38:27017",
                         "arbiterOnly" : false,
                         "buildIndexes" : true,
                         "hidden" : false,
                         "priority" : 1,
                         "tags" : {

                         },
                         "slaveDelay" : 0,
                         "votes" : 1
                 },
                 {
                         "_id" : 2,
                         "host" : "172.17.4.39:27017",
                         "arbiterOnly" : false,
                         "buildIndexes" : true,
                         "hidden" : false,
                         "priority" : 3,             //優先級變為3
                         "tags" : {

                         },
                         "slaveDelay" : 0,
                         "votes" : 1
                 }
         ],
         "settings" : {
                 "chainingAllowed" : true,
                 "heartbeatTimeoutSecs" : 10,
                 "getLastErrorModes" : {

                 },
                 "getLastErrorDefaults" : {
                         "w" : 1,
                         "wtimeout" : 0
                 }
         }
 }

 arps:SECONDARY> rs.status()
 {
         "set" : "arps",
         "date" : ISODate("2017-12-22T07:25:04.641Z"),
         "myState" : 2,
         "syncingTo" : "172.17.4.39:27017",
         "members" : [
                 {
                         "_id" : 0,
                         "name" : "172.17.4.37:27017",
                         "health" : 1,
                         "state" : 2,
                         "stateStr" : "SECONDARY",
                         "uptime" : 7597536,
                         "optime" : Timestamp(1513927481, 3),
                         "optimeDate" : ISODate("2017-12-22T07:24:41Z"),
                         "syncingTo" : "172.17.4.39:27017",
                         "configVersion" : 4,
                         "self" : true
                 },
                 {
                         "_id" : 1,
                         "name" : "172.17.4.38:27017",
                         "health" : 1,
                         "state" : 2,
                         "stateStr" : "SECONDARY",
                         "uptime" : 7597426,
                         "optime" : Timestamp(1513927481, 3),
                         "optimeDate" : ISODate("2017-12-22T07:24:41Z"),
                         "lastHeartbeat" : ISODate("2017-12-22T07:25:02.961Z"),
                         "lastHeartbeatRecv" : ISODate("2017-12-22T07:25:04.091Z"),
                         "pingMs" : 0,
                         "syncingTo" : "172.17.4.39:27017",
                         "configVersion" : 4
                 },
                 {
                         "_id" : 2,
                         "name" : "172.17.4.39:27017",
                         "health" : 1,
                         "state" : 1,
                         "stateStr" : "PRIMARY",    //最后一個節點升級為PRIMARY
                         "uptime" : 3202,
                         "optime" : Timestamp(1513927481, 3),
                         "optimeDate" : ISODate("2017-12-22T07:24:41Z"),
                         "lastHeartbeat" : ISODate("2017-12-22T07:25:02.951Z"),
                         "lastHeartbeatRecv" : ISODate("2017-12-22T07:25:04.344Z"),
                         "pingMs" : 0,
                         "electionTime" : Timestamp(1513927190, 2),
                         "electionDate" : ISODate("2017-12-22T07:19:50Z"),
                         "configVersion" : 4
                 }
         ],
         "ok" : 1
 }

 

整理自：

https://www.cnblogs.com/ivictor/p/6804408.html

http://blog.chinaunix.net/uid-26446098-id-5781440.html