mongodb - mongo authentication failed

Question

2016-11-09T21:44:08.312 0800 I ACCESS [conn2] SCRAM-SHA-1 authentication failed for on mytestdatabase from client 127.0.0.1 ; BadValue: Incorrect SCRAM-SHA-1 user name: n=

2016-11-09T21:44:08.779 0800 I NETWORK [conn2] end connection 127.0.0.1:51739 (1 connection now open)
2016-11-09T21:44:08.779 0800 I NETWORK [conn1 ] end connection 127.0.0.1:51737 (1 connection now open)

mac osx 10.10.5

mongodb-osx-x86_64-3.2.4

mongo-java-driver-2.13.1

Use nutch to execute the first task InjectorJob

The above is an error message. What is the reason?