I'm trying to install Mongodb on Ubuntu 12 but when I run this command: sudo apt-key adv --keyserver keyserver.ubuntu.com --recv 7F0CEB10 This returned the error below: keyserver.ubuntu.com host not found gpgkeys: HTTP fetch error 7: couldn't connect: no such file or directory gpg:no valid openPGP data found gpg: Total number processes :0 I turned off Firewall on Iptables, but it don't work. Is there any idea?