I am running Fedora 20 and installed MongoDB per the Red Hat installation guide on the official documentation. I was able to run the mongod
daemon as a service with
I've spent a while looking into this, and it appears as if the pid folder and file permissions don't work with the default daemon.
The simplest solution I've come across is disable the pid file by just putting a # in front of the line in the config file.
vi /etc/mongod.conf
find the line that says pidfilepath=/var/run/mongodb/mongod.pid and change it accordingly.
# pidfilepath=/var/run/mongodb/mongod.pid
For information on what commenting it out does check here. http://docs.mongodb.org/manual/reference/configuration-options/#processManagement.pidFilePath