gistfile1.txt

sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv 7F0CEB10
echo 'deb http://downloads-distro.mongodb.org/repo/ubuntu-upstart dist 10gen' | sudo tee /etc/apt/sources.list.d/mongodb.list
sudo apt-get update
sudo apt-get install mongodb-org

db.getSiblingDB("admin").runCommand({authSchemaUpgrade: 1 });

http://docs.mongodb.org/manual/release-notes/2.6-upgrade-authorization/

apt-get install mongodb-org=3.0.2 mongodb-org-mongos=3.0.2 mongodb-org-server=3.0.2 mongodb-org-shell=3.0.2 mongodb-org-tools=3.0.2

apt-get install mongodb-org=2.6.9 mongodb-org-mongos=2.6.9 mongodb-org-server=2.6.9 mongodb-org-shell=2.6.9 mongodb-org-tools=2.6.9

echo "deb http://repo.mongodb.org/apt/ubuntu "$(lsb_release -sc)"/mongodb-org/3.0 multiverse" | sudo tee /etc/apt/sources.list.d/mongodb-org-3.0.list

http://docs.mongodb.org/master/tutorial/install-mongodb-on-ubuntu/