Mongodb wont start ERROR: child process failed, exited with

[a24uall]

After installation mongodb wont start and the error I receive is :
Starting mongod: about to fork child process, waiting until server is ready for connections.
ERROR: child process failed, exited with error number 100

Error log shows :

ERROR: Insufficient free space for journal files

[root@ip-172-31-45-60 ~]# service mongod restart
Stopping mongod: [FAILED]
Starting mongod: about to fork child process, waiting until server is ready for connections.
forked process: 14602
all output going to: /var/log/mongo/mongod.log
ERROR: child process failed, exited with error number 100
[FAILED]
[root@ip-172-31-45-60 ~]#

Solution :

First run

mongod --smallfiles

vi /etc/mongod.conf

Add or uncomment

nojournal = true

Save and restart mongodb

[root@ip-172-31-45-60 ~]# service mongod restart
Stopping mongod: [FAILED]
Starting mongod: about to fork child process, waiting until server is ready for connections.
forked process: 15098
all output going to: /var/log/mongo/mongod.log
child process started successfully, parent exiting
[ OK ]
[root@ip-172-31-45-60 ~]#