How do you secure your mongodb database?

Steps to secure mongo database. I will assume everything is configured and properly working.

1. show dbs to list down available databases
2. use admin to select admin database so we can create root user first.

3. db.createUser({
                          user: 'adminusername',
                           pwd: passwordPrompt() || "plainPassword"            i.e use  passwordPrompt() if mongodb version is >= 4.2
                          roles: [{role: "userAdminAnyDatabase", db: "admin"}, "readWriteAnyDatabase"]
      })

   i.e if everything is fine, you will be prompted to enter a password.

4.  After this configuration go ahead and enable authentication on mongodb conf file.                     if you are using ubuntu go ahead and edit /etc/mongod.conf (i.e if in windows mongo/4.4/bin/mongod.cfg) uncomment security section Then add the authorization parameter and set it to enabled.                                                                    . . .
   security:
   authorization: enabled
   . . .                                                                                                                                                            then save and exit from the editor
5.  sudo systemctl restart mongodb  restart your mongodb service so that the changes take effect. i.e if you are on windows go to services.msc  and restart mongodb service.