replica set多服務器主從，添加，刪除節點，肯定會經常遇到的。下面詳細說明一下，添加，刪除節點的2種方法。
一，利用rs.reconfig，來添加，刪除節點
1，添加節點
代碼如下repmore:PRIMARY> config = {_id:"repmore",members:[{_id:0,host:'127.0.0.1:27017',priority :2},{_id:1,host:'127.0.0.1:27018',priority:1}]}; //添加節點
repmore:PRIMARY> rs.reconfig(config); //使配置生效
repmore:PRIMARY> rs.status(); //查看節點狀態
節點添加成功。
注意：新增節點的replSet要和其他節點要一樣
2,刪除節點(刪除節點前最好是先關閉需要刪除的節點，之後通過命令 rs.remove 來刪除)
代碼如下repmore:PRIMARY> config = {_id:"repmore",members:[{_id:0,host:'127.0.0.1:27017',priority :2}]}; //刪除節點
repmore:PRIMARY> rs.reconfig(config); //使配置生效
repmore:PRIMARY> rs.status(); //查看節點狀態
二，利用rs.add和rs.remove來添加刪除節點
代碼如下repmore:PRIMARY> rs.add("127.0.0.1:27018"); //添加節點
repmore:PRIMARY> rs.remove("127.0.0.1:27018"); //刪除節
注意：利用rs.add和rs.remove是不用rs.reconfig來使用配置生效的。
最後對於刪除節點我這裡再附一個標准流程給各位
相應的節點，操作如下：
代碼如下--1 查看當前 Replica Set 配置
[mongo@redhatB mongodb]$ mongo 127.0.0.1:27018
MongoDB shell version: 2.2.1
connecting to: 127.0.0.1:27018/test
rs0:PRIMARY> rs.conf();
{
"_id" : "rs0",
"version" : 4,
"members" : [
{
"_id" : 0,
"host" : "redhatB.example.com:27018"
},
{
"_id" : 1,
"host" : "redhatB.example.com:27019"
},
{
"_id" : 2,
"host" : "redhatB.example.com:27020"
},
{
"_id" : 3,
"host" : "redhatB.example.com:27021"
}
]
}
備注：計劃刪除節點 "_id" : 3。
--2 關閉 27021 節點服務
[mongo@redhatB data04]$ ps -ef | grep 27021
mongo 11733 1 0 21:03 ? 00:00:15 mongod -f /pgdata_xc/mongodb/data04/mongodb_27021.conf
mongo 14422 2953 0 21:53 pts/0 00:00:00 mongo 127.0.0.1:27021
mongo 14490 4027 0 21:54 pts/1 00:00:00 grep 27021
[mongo@redhatB data04]$ kill 11733
--3 查看 replica set 狀態
rs0:PRIMARY> rs.status();
{
"set" : "rs0",
"date" : ISODate("2012-11-22T13:57:15Z"),
"myState" : 1,
"members" : [
{
"_id" : 0,
"name" : "redhatB.example.com:27018",
"health" : 1,
"state" : 1,
"stateStr" : "PRIMARY",
"uptime" : 21279,
"optime" : Timestamp(1353589624000, 1),
"optimeDate" : ISODate("2012-11-22T13:07:04Z"),
"self" : true
},
{
"_id" : 1,
"name" : "redhatB.example.com:27019",
"health" : 1,
"state" : 2,
"stateStr" : "SECONDARY",
"uptime" : 18908,
"optime" : Timestamp(1353589624000, 1),
"optimeDate" : ISODate("2012-11-22T13:07:04Z"),
"lastHeartbeat" : ISODate("2012-11-22T13:57:13Z"),
"pingMs" : 0
},
{
"_id" : 2,
"name" : "redhatB.example.com:27020",
"health" : 1,
"state" : 2,
"stateStr" : "SECONDARY",
"uptime" : 18900,
"optime" : Timestamp(1353589624000, 1),
"optimeDate" : ISODate("2012-11-22T13:07:04Z"),
"lastHeartbeat" : ISODate("2012-11-22T13:57:14Z"),
"pingMs" : 0
},
{
"_id" : 3,
"name" : "redhatB.example.com:27021",
"health" : 0,
"state" : 8,
"stateStr" : "(not reachable/healthy)",
"uptime" : 0,
"optime" : Timestamp(1353589624000, 1),
"optimeDate" : ISODate("2012-11-22T13:07:04Z"),
"lastHeartbeat" : ISODate("2012-11-22T13:55:20Z"),
"pingMs" : 0,
"errmsg" : "socket exception [CONNECT_ERROR] for redhatB.example.com:27021"
}
],
"ok" : 1
}
備注：最後一個節點 stateStr 狀態為 “not reachable/healthy”。
--4 刪除節點
rs0:PRIMARY> rs.remove("redhatB.example.com:27021");
Thu Nov 22 21:58:45 DBClientCursor::init call() failed
Thu Nov 22 21:58:45 query failed : admin.$cmd { replSetReconfig: { _id: "rs0", version: 5, members: [ { _id: 0, host: "redhatB.example.com:27018" }, { _id: 1, host: "redhatB.example.com:27019" }, { _id: 2, host: "redhatB.example.com:27020" } ] } } to: 127.0.0.1:27018
Thu Nov 22 21:58:45 Error: error doing query: failed src/mongo/shell/collection.js:155
Thu Nov 22 21:58:45 trying reconnect to 127.0.0.1:27018
Thu Nov 22 21:58:45 reconnect 127.0.0.1:27018 ok
rs0:SECONDARY>
rs0:PRIMARY>
--5 再次查看 replica set 配置
rs0:PRIMARY> rs.conf();
{
"_id" : "rs0",
"version" : 5,
"members" : [
{
"_id" : 0,
"host" : "redhatB.example.com:27018"
},
{
"_id" : 1,
"host" : "redhatB.example.com:27019"
},
{
"_id" : 2,
"host" : "redhatB.example.com:27020"
}
]
}
備注：節點 "redhatB.example.com:27021" 已刪除。
--6 刪除舊結點數據目錄
代碼如下[mongo@redhatB mongodb]$ rm -rf /mongodb/data04
