You say you did this:
Instead of using the system provided MongoDB which is 2.4, I want to use 2.6 so I downloaded MongoDB executable and just put it in the places I wanted.
That’s really not the supported and recommended way you should be installing MongoDB on your system. The MongoDB team is very well aware that official Linux repositories don’t always keep up to date with latest releases of many packages, so they provide their own PPA for MongoDB as explained here. I would recommend removing whatever you just installed and follow these steps instead.
First, import the public key used by the package management system:
sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv 7F0CEB10
Then create a sources list file for MongoDB:
echo 'deb http://downloads-distro.mongodb.org/repo/ubuntu-upstart dist 10gen' | sudo tee /etc/apt/sources.list.d/mongodb.list
Now run apt-get
with update
to refresh the sources list:
sudo apt-get update
And finally, install MongoDB directly from the repository like this:
sudo apt-get install -y mongodb-org