mongodb 分片集群切换单个分片副本集primary的正确步骤

1、将原来的primay降为secondary

shard1:PRIMARY> rs.stepDown(); 2016-07-11T20:35:30.134+0800 I NETWORK DBClientCursor::init call() failed 2016-07-11T20:35:30.141+0800 E QUERY Error: error doing query: failed at DBQuery._exec (src/mongo/shell/query.js:83:36) at DBQuery.hasNext (src/mongo/shell/query.js:240:10) at DBCollection.findOne (src/mongo/shell/collection.js:187:19) at DB.runCommand (src/mongo/shell/db.js:58:41) at DB.adminCommand (src/mongo/shell/db.js:66:41) at Function.rs.stepDown (src/mongo/shell/utils.js:1006:15) at (shell):1:4 at src/mongo/shell/query.js:83 2016-07-11T20:35:30.144+0800 I NETWORK trying reconnect to 10.2.3.63:27017 (10.2.3.63) failed 2016-07-11T20:35:30.146+0800 I NETWORK reconnect 10.2.3.63:27017 (10.2.3.63) ok shard1:SECONDARY>

2、移除原来的primay库

如果不及时使用rs.remove移除旧的主库的话，mongodb运行中有一定概率会将旧的主库自动从secondary升级为primary的，所以一旦primary切换成功后，需要remove旧的primary库以防万一。

Remove执行过程如下： [mongodb@db_m1_slave_1 ~]$ /usr/local/mongodb-linux-x86_-3.0.3/bin/mongo 10.2.3.72:27027 MongoDB shell version: 3.0.3 connecting to: 10.2.3.72:27027/test shard1:PRIMARY> rs.remove(\"10.2.3.63:27017\"); 2016-07-11T20:36:01.314+0800 I NETWORK DBClientCursor::init call() failed 2016-07-11T20:36:01.323+0800 E QUERY Error: error doing query: failed at DBQuery._exec (src/mongo/shell/query.js:83:36) at DBQuery.hasNext (src/mongo/shell/query.js:240:10) at DBCollection.findOne (src/mongo/shell/collection.js:187:19) at DB.runCommand (src/mongo/shell/db.js:58:41) at DB.adminCommand (src/mongo/shell/db.js:66:41) at Function.rs.remove (src/mongo/shell/utils.js:1031:23) at (shell):1:4 at src/mongo/shell/query.js:83 2016-07-11T20:36:01.326+0800 I NETWORK trying reconnect to 10.2.3.72:27027 (10.2.3.72) failed 2016-07-11T20:36:01.327+0800 I NETWORK reconnect 10.2.3.72:27027 (10.2.3.72) ok shard1:PRIMARY> shard1:PRIMARY> shard1:PRIMARY> rs.status(); { \"set\" : \"shard1\ \"date\" : ISODate(\"2016-07-11T12:36:20Z\"), \"myState\" : 1, \"members\" : [ { \"_id\" : 0, \"name\" : \"10.2.3.62:27017\ \"health\" : 1, \"state\" : 2, \"stateStr\" : \"SECONDARY\ \"uptime\" : 19, \"optime\" : Timestamp(1468240561, 1), \"optimeDate\" : ISODate(\"2016-07-11T12:36:01Z\"), \"lastHeartbeat\" : ISODate(\"2016-07-11T12:36:19Z\"), \"lastHeartbeatRecv\" : ISODate(\"2016-07-11T12:36:20Z\"), \"pingMs\" : 0, \"lastHeartbeatMessage\" : \"syncing to: 10.2.3.72:27027\ \"syncingTo\" : \"10.2.3.72:27027\" }, { \"_id\" : 2, \"name\" : \"10.2.3.72:27017\ \"health\" : 1, \"state\" : 7, \"stateStr\" : \"ARBITER\ \"uptime\" : 19, \"lastHeartbeat\" : ISODate(\"2016-07-11T12:36:19Z\"), \"lastHeartbeatRecv\" : ISODate(\"2016-07-11T12:36:20Z\"), \"pingMs\" : 0 }, { \"_id\" : 3, \"name\" : \"10.2.3.72:27027\ \"health\" : 1, \"state\" : 1, \"stateStr\" : \"PRIMARY\ \"uptime\" : 33237, \"optime\" : Timestamp(1468240561, 1), \"optimeDate\" : ISODate(\"2016-07-11T12:36:01Z\"), \"self\" : true } ], \"ok\" : 1 } shard1:PRIMARY>

3、查看副本集新运行状态

[mongodb@db_m2_slave1 ~]$ /usr/local/mongodb-linux-x86_-3.0.3/bin/mongo 10.2.3.72:27027 MongoDB shell version: 3.0.3 connecting to: 10.2.3.72:27027/test shard1:PRIMARY> rs.status(); { \"set\" : \"shard1\ \"date\" : ISODate(\"2016-07-11T14:13:37Z\"), \"myState\" : 1, \"members\" : [ { \"_id\" : 0, \"name\" : \"10.2.3.62:27017\ \"health\" : 1, \"state\" : 2, \"stateStr\" : \"SECONDARY\ \"uptime\" : 5856, \"optime\" : Timestamp(14682415, 1), \"optimeDate\" : ISODate(\"2016-07-11T14:13:35Z\"), \"lastHeartbeat\" : ISODate(\"2016-07-11T14:13:36Z\"), \"lastHeartbeatRecv\" : ISODate(\"1970-01-01T00:00:00Z\"), \"pingMs\" : 4, \"syncingTo\" : \"10.2.3.72:27027\" }, { \"_id\" : 2, \"name\" : \"10.2.3.72:27017\ \"health\" : 1, \"state\" : 7, \"stateStr\" : \"ARBITER\ \"uptime\" : 5856, \"lastHeartbeat\" : ISODate(\"2016-07-11T14:13:36Z\"), \"lastHeartbeatRecv\" : ISODate(\"1970-01-01T00:00:00Z\"), \"pingMs\" : 0 }, { \"_id\" : 3, \"name\" : \"10.2.3.72:27027\ \"health\" : 1, \"state\" : 1, \"stateStr\" : \"PRIMARY\ \"uptime\" : 39074, \"optime\" : Timestamp(14682415, 1), \"optimeDate\" : ISODate(\"2016-07-11T14:13:35Z\"), \"self\" : true } ], \"ok\" : 1 } shard1:PRIMARY>

参考文档地址：http://docs.mongoing.com/manual-zh/reference/configuration-options.html