我有一个包含3个成员的简单副本集
rs.status()
的输入{
...,
"members" : [
{
"_id": 1,
"name": "localhost:27021",
"stateStr": "PRIMARY",
},
{
"_id": 2,
"name": "localhost:27022",
"stateStr": "SECONDARY",
},
{
"_id": 3,
"name": "localhost:27023",
"stateStr": "SECONDARY",
}
]
}
我删除了一名成员
rs.remove("localhost:27023")
现在 rs.status()
{
...,
"members" : [
{
"_id": 1,
"name": "localhost:27021",
"stateStr": "PRIMARY",
},
{
"_id": 2,
"name": "localhost:27022",
"stateStr": "SECONDARY",
},
]
}
现在,我将mongodb连接URL用于已删除的实例。它成功连接到副本集成员!!
var url = 'mongodb://localhost:27023/myproject?replicaSet=rs0';
MongoClient.connect(url, function(err, db) {
console.log("Connected correctly to server");
db.close();
});
我可以看到该连接是使用副本集成员(localhost:27022和localhost:27023)建立的
2019-04-17T18:59:04.727+0900 I NETWORK [thread1] connection accepted from 127.0.0.1:53284 #6 (3 connections now open)
2019-04-17T18:59:04.727+0900 I NETWORK [conn6] received client metadata from 127.0.0.1:53284 conn6: { driver: { name: "nodejs", version: "3.2.3" }, os: { type: "Linux", name: "linux", architecture: "x64", version: "4.15.0-47-generic" }, platform: "Node.js v10.15.0, LE, mongodb-core: 3.2.3" }
2019-04-17T18:59:04.736+0900 I - [conn6] end connection 127.0.0.1:53284 (3 connections now open)
2019-04-17T18:59:35.334+0900 I ASIO [NetworkInterfaceASIO-RS-0] Ending idle connection to host localhost:27021 because the pool meets constraints; 1 connections to that host remain open
有人可以解释吗? 通过已删除的成员连接到副本集成员。 在任何文档中都找不到任何解释。
答案 0 :(得分:3)
这是驱动程序行为。默认情况下,客户端连接到副本集将尝试连接到主节点。在这种情况下,连接到mongodb://localhost:27023/myproject?replicaSet=rs0
将首先连接到localhost:27023
,并使用命令{isMaster: 1}
检查连接的节点是主节点还是主节点。从结果中,它检测到localhost:27023
不是主节点/主节点,但它还有其他可用节点信息。下一步是连接到其他节点,直到找到主要节点为止。
您应该关闭localhost:27023
,它甚至都不会连接。