log 日志错误信息
2018-10-24T16:14:42.244+0800 I NETWORK [initandlisten] connection accepted from 192.168.1.198:37354 #165 (2 connections now open)
2018-10-24T16:14:42.250+0800 I ACCESS [conn165] SCRAM-SHA-1 authentication failed for djx123 on djx_test from client 172.16.2.208 ; UserNotFound Could not find user djx123@djx_test
2018-10-24T16:14:42.253+0800 I NETWORK [conn165] end connection 192.168.1.198:37354 (1 connection now open)
2018-10-24T16:14:42.756+0800 I NETWORK [initandlisten] connection accepted from 192.168.1.198:37356 #166 (2 connections now open)
2018-10-24T16:14:42.762+0800 I ACCESS [conn166] SCRAM-SHA-1 authentication failed for djx123 on djx_test from client 172.16.2.208 ; UserNotFound Could not find user djx123@djx_test
2018-10-24T16:14:42.765+0800 I NETWORK [conn166] end connection 192.168.1.198:37356 (1 connection now open)
2018-10-24T16:14:43.268+0800 I NETWORK [initandlisten] connection accepted from 192.168.1.198:37358 #167 (2 connections now open)
2018-10-24T16:14:43.274+0800 I ACCESS [conn167] SCRAM-SHA-1 authentication failed for djx123 on djx_test from client 172.16.2.208 ; UserNotFound Could not find user djx123@djx_test
mongodb 加入了SCRAM-SHA-1校验方式，需要第三方工具配合进行验证，下面给出具体解决办法：
首先关闭认证（noauth = yes），修改system.version文档里面的authSchema版本为3，初始安装时候应该是5，命令行如下：
> use admin
switched to db admin
> var schema = db.system.version.findOne({"_id" : "authSchema"})
> schema.currentVersion = 3
3
> db.system.version.save(schema)
WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 })
更改后用之前的用户进行登录的话还是登录不了，因为之前之前的用户是基于之前的认证生成的，
我们将之前的用户删除，删除后重新创建用户
重新连接，成功。
可以查看一下链接介绍：
https://docs.mongodb.com/master/release-notes/3.0-scram/
还有国外友人的回答：
http://stackoverflow.com/questions/29006887/mongodb-cr-authentication-failed
本文转自https://www.cnblogs.com/timelesszhuang/p/5668589.html
