mongodb之副本集的實現及故障自動轉移

Mongodb之副本集的實現----repliSet

準備三個節點：

RS1：192.168.1.155：27017

RS2：192.168.1.11:27017

node1:192.168.1.112:27017

1、時間同步

ntpdate192.168.1.11

2、安裝mongodb服務

rpm包地址：https://repo.mongodb.org/yum/redhat

yum –y localinstall*.rpm

mkdir –p/mongodb/data

chown –Rmongod:mongod /mongodb/data

usermod –d/mongodb/data mongod

3、修改配置文件

vim /etc/mongod.conf

#dbPath:/var/lib/mongo

  dbPath: /mongodb/data

replication:啟用這項

  replSetName: testrs：給副本集定義一個名稱

然后同步到另外兩個節點

4、啟動mongod服務

service mongodstart

選擇192.168.1.155:27017這個服務登錄

mongo

help---àrs.help()---àrs.initiate()用此命令進行初始化

發現報錯如下：

該主機映射不到節點上，進行谷歌搜索查到原因，由于配置文件bindip綁定的是127.0.0.1上，而/etc/hosts文件中127.0.0.1余hostname---》RS1并沒有指定關聯于是做此修改

127.0.0.1   localhost localhost.localdomain localhost4localhost4.localdomain4 RS1

在最后加上hostname，于是重新初始化，發現果然解決問題

5、由于上步驟已經把服務都啟動起來了，于是繼續在192.168.1.155上進行添加主機

Rs.add(‘192.168.1.11:27017’)--à發現又報錯，如下圖

可以看出連接不上另外的節點，在155節點上進行嘗試登陸

mongo  --host 192.168.1.11 –port 27017發現還是登陸不上，翻看很多文章，描述的都不是很詳細，于是一個群友解決了疑惑，由于配置文件中bindip并沒有進行修改只是監聽的127.0.0.1，在一個系統中配置三個實例mongodb這種方式可以不用修改，但是現在是三臺不同的系統ip，于是得進行修改

net:

  port: 27017

  bindIp: 192.168.1.155將其他兩個節點也進行修改，添加為本機ip，而不是127.0.0.1，（當然bindip也可以綁定多個ip：192.168.1.155 127.0.0.1）然后在hosts文件中加入：

192.168.1.155  RS1

192.168.1.11  RS2

192.168.1.112  node1

完成以上步驟之后，然后進行再次添加

rs.add(‘192.168.1.11:27017’)-à

testrs:PRIMARY>rs.add('192.168.1.11:27017')

{ "ok": 1 }:沒有報錯于是成功

然后再次添加下個節點

rs.add(‘192.168.1.112:27017’)

rs.status()：進行查看節點間的狀態

testrs:PRIMARY>rs.status()

{

      "set" : "testrs",

      "date" : ISODate("2016-07-26T04:21:32.729Z"),

      "myState" : 1,

      "term" : NumberLong(3),

      "heartbeatIntervalMillis" :NumberLong(2000),

      "members" : [

           {

                 "_id" : 0,

                 "name" :"RS1:27017",

                 "health" : 1,

                 "state" : 1,

                 "stateStr" :"PRIMARY",：主節點

                 "uptime" : 346,

                 "optime" : {

                      "ts" :Timestamp(1469506890, 1),

                      "t" :NumberLong(3)

                 },

                 "optimeDate" :ISODate("2016-07-26T04:21:30Z"),

                 "electionTime" :Timestamp(1469506554, 1),

                 "electionDate" :ISODate("2016-07-26T04:15:54Z"),

                 "configVersion" : 3,

                 "self" : true

           },

           {

                 "_id" : 1,

                 "name" :"192.168.1.11:27017",

                 "health" : 1,

                 "state" : 2,

                 "stateStr" :"SECONDARY",：從節點

                 "uptime" : 156,

                 "optime" : {

                      "ts" :Timestamp(1469506735, 1),

                      "t" :NumberLong(3)

                 },

                 "optimeDate" :ISODate("2016-07-26T04:18:55Z"),

                 "lastHeartbeat" :ISODate("2016-07-26T04:21:30.870Z"),

                 "lastHeartbeatRecv" :ISODate("2016-07-26T04:21:30.974Z"),

                 "pingMs" :NumberLong(1),

                 "configVersion" : 2

           },

           {

                 "_id" : 2,

                 "name" : "192.168.1.112:27017",

                 "health" : 1,

                 "state" : 0,

                 "stateStr" :"STARTUP",：由于是剛剛添加，正在開啟

                 "uptime" : 1,

                 "optime" : {

                      "ts" :Timestamp(0, 0),

                      "t" :NumberLong(-1)

                 },

                 "optimeDate" :ISODate("1970-01-01T00:00:00Z"),

                 "lastHeartbeat" :ISODate("2016-07-26T04:21:31.165Z"),

                 "lastHeartbeatRecv" :ISODate("2016-07-26T04:21:32.498Z"),

                 "pingMs" :NumberLong(193),

                 "configVersion" : -2

           }

      ],

      "ok" : 1

}

至此，副本集已然完成，接下來就是驗證主從是否同步？

6、在192.168.1.155:27017主節點上一次進行如下操作：

testrs:PRIMARY>use huangdb:切換到庫

switched to dbhuangdb

testrs:PRIMARY>show collections

testcoll

testrs:PRIMARY>db.testcoll.find()

{"_id" : ObjectId("5792d2a3a4769176f5babaaa"),"Name" : "huang", "Age" : 24, "Gender": "F" }

testrs:PRIMARY>db.testcoll.insert({Name:"xiaoming",Age:23,url:"www.baidu.com"})

WriteResult({"nInserted" : 1 })：添加一條文檔記錄

testrs:PRIMARY>db.testcoll.find()：查看文檔記錄

{"_id" : ObjectId("5792d2a3a4769176f5babaaa"),"Name" : "huang", "Age" : 24, "Gender": "F" }

{"_id" : ObjectId("5796e7333f3249e9b0b44ded"),"Name" : "xiaoming", "Age" : 23, "url": "www.baidu.com" }

然后在192.168.1.11:27017上這個系統進行登錄驗證

mongo –host 192.168.1.11–port 27017

use huangdb

show collections發現報錯如下：

根據報錯提示進行

rs.slaveOk()

然后進行查看

Db.testcoll.find()于是可以看見集合的內容記錄，至此主從同步ok

7、接下來就是觀察節點間能否進行failover故障轉移

將192.168.1.155的mongod服務停止

[root@RS1 ~]#service mongod stop

Stoppingmongod:                                           [確定]

于是在192.168.1.11上查看副本集狀態

testrs:SECONDARY>rs.status()

{

      "set" : "testrs",

      "date" : ISODate("2016-07-26T05:06:39.686Z"),

      "myState" : 2,

      "term" : NumberLong(4),

      "syncingTo" :"192.168.1.112:27017",

      "heartbeatIntervalMillis" :NumberLong(2000),

      "members" : [

           {

                 "_id" : 0,

                 "name" :"RS1:27017",

                 "health" : 0,

                 "state" : 8,

                 "stateStr" :"(not reachable/healthy)",

                 "uptime" : 0,

                 "optime" : {

                      "ts" :Timestamp(0, 0),

                      "t" :NumberLong(-1)

                 },

                 "optimeDate" :ISODate("1970-01-01T00:00:00Z"),

                 "lastHeartbeat" :ISODate("2016-07-26T05:06:39.641Z"),

                 "lastHeartbeatRecv" :ISODate("2016-07-26T05:05:58.844Z"),

                 "pingMs" :NumberLong(2),

                 "lastHeartbeatMessage": "Connection refused",

                 "configVersion" : -1

           },

           {

                 "_id" : 1,

                 "name" :"192.168.1.11:27017",

                 "health" : 1,

                 "state" : 2,

                 "stateStr" : "SECONDARY",

                 "uptime" : 3019,

                 "optime" : {

                      "ts" :Timestamp(1469509568, 2),

                      "t" :NumberLong(4)

                 },

                 "optimeDate" :ISODate("2016-07-26T05:06:08Z"),

                 "syncingTo" :"192.168.1.112:27017",

                 "configVersion" : 3,

                 "self" : true

           },

           {

                 "_id" : 2,

                 "name" :"192.168.1.112:27017",

                 "health" : 1,

                 "state" : 1,

                 "stateStr" :"PRIMARY",

                 "uptime" : 2708,

                 "optime" : {

                      "ts" :Timestamp(1469509568, 2),

                      "t" :NumberLong(4)

                 },

                 "optimeDate" :ISODate("2016-07-26T05:06:08Z"),

                 "lastHeartbeat" :ISODate("2016-07-26T05:06:38.433Z"),

                 "lastHeartbeatRecv" :ISODate("2016-07-26T05:06:38.907Z"),

                 "pingMs" :NumberLong(1),

                 "electionTime" :Timestamp(1469509568, 1),

                 "electionDate" :ISODate("2016-07-26T05:06:08Z"),

                 "configVersion" : 3

           }

      ],

      "ok" : 1

}

根據狀態可以看出192.168.1.155狀態已經不健康了，而192.168.1.112從從節點勁升為了主節點，于是故障自動轉移成功