I have been test driving mongodb with some serious projects. I have always had difficulty in creating users in any database. Mongodb was no surprise. Here is the working command for me.

  • Error 2016-02-16T01:28:27.570+0000 Error: couldn’t add user: User “test1@admin” already exists at src/mongo/shell/db.js:1004

  • First add the user: mongo localhost:12346

> use admin

> db.createUser({ user: "test1", pwd: "test", roles:[ { role: "readWrite", db: "isimibul-dev" }]})

  • Now connect by using the user:

mongo localhost:12346/mydb-dev -u test1 -p test

One side note: If you are having difficulties with connecting to the DB, you can change auth mechanism to MONGODB-CR, this is the old system used back in the days of v2.4; now SHA is used for auth, if you are using an updated version like v3, just use SHA as auth mechanism.