這幾天一直在折騰mongodb數據庫，一直出現如下這個問題

MongoDB shell version v3.6.0
connecting to: mongodb://127.0.0.1:27017
2017-12-27T09:54:34.775+0800 W NETWORK [thread1] Failed to connect to 127.0.0.1:27017, in(checking socket for error after poll), reason: Connection refused
2017-12-27T09:54:34.778+0800 E QUERY [thread1] Error: couldn‘t connect to server 127.0.0.1:27017, connection attempt failed :
connect@src/mongo/shell/mongo.js:237:13
@(connect):1:6
exception: connect failed
 

嘗試各種方法都不行

當mongodb service 沒有運行的時候會發生這樣的錯誤

嘗試了新建一個/data/db 目錄，也不奏效。

後來通過搜索，尋找到來解決方法，運行命令

brew services start mongodb

再去調用數據庫命令

mongo

就可以完美解決問題了

最終mac下顯示成功的提示

MongoDB shell version v3.6.0
connecting to: mongodb://127.0.0.1:27017
MongoDB server version: 3.6.0
Server has startup warnings: 
2017-12-27T09:54:58.316+0800 I CONTROL  [initandlisten] 
 
2017-12-27T09:54:58.316+0800 I CONTROL  [initandlisten] ** WARNING: Access control is not enabled for the database.
2017-12-27T09:54:58.316+0800 I CONTROL  [initandlisten] **          Read and write access to data and configuration is unrestricted.
2017-12-27T09:54:58.316+0800 I CONTROL  [initandlisten] 
> 

Mac下mongodb connect failed 連接錯誤解決方法