Mongodb – how to set mogodb in upstart service with authentication in mongodb way

The solution to this issue was as follows: Starting with the secondary:

Inside of Mongo I ran the following:

db.shutdownServer()
exit

On the command line:

rm -rf /var/lib/mongodb/*
sudo service mongodb start

It then takes a couple of hours to resync. Once resynced I did the following on the primary:

rs.status() //To make sure that the everything was synced
rs.stepDown(9200)
db.shutdownServer()
exit

On the command line I ran:

rm -rf /var/lib/mongodb/*
sudo service mongodb start

Then in Mongo I ran:

rs.status() //To make sure that everything was synced
rs.freeze(0) //To remove the re.stepDown(9200) lock

On the secondary I ran:

rs.stepDown()

Note: If possible, back up all of your data first.

I wasn't able to use wiredTiger upgrading MongoDB. However, at May 17 I uninstalled MongoDB 2.6 then installed MongoDB 3.0.3 . Immediate after the installation, I added storageEngine=wiredTiger on top of my mongod.conf file. Then I gave sudo service mongod start command and eventually I could.

Edit:

For fresh installed as directed by official documentation;

1. Open configuration file using sudo nano /etc/mongod.conf
2. Change the # engine line to engine: wiredTiger like the below
3. Run mongod using the command sudo service mongod start

.

# Where and how to store data.
storage:
  dbPath: /var/lib/mongodb
  journal:
    enabled: true
  engine: wiredTiger
#  mmapv1:
#  wiredTiger:

Edit:

If the current version is supported the wiredTiger;

1. Get the backup of the current database using mongodump command
2. Stop the mongod service using sudo service mongod stop command
3. Add storageEngine=wiredTiger text as the first line of mongod.conf file
4. Delete the all file on /var/lib/mongodb (or /data/db folder if used)
   [This is important. Because MongoDB cannot convert the current MMAP db files to wiredTiger format]
5. Start the mongod service using sudo service mongod start command
6. Restore the database from the backup using [mongorestore][2] command
7. wiredTiger is being used...