W: Failed to fetch http://ftp.uninett.no/ubuntu/dists/raring/Release.gpg  Something wicked happened resolving 'ftp.uninett.no:http' (-11 - System error)

W: Failed to fetch http://ftp.uninett.no/ubuntu/dists/raring-updates/Release.gpg  Something wicked happened resolving 'ftp.uninett.no:http' (-11 - System error)

W: Failed to fetch http://archive.canonical.com/ubuntu/dists/raring/Release.gpg  Something wicked happened resolving 'archive.canonical.com:http' (-11 - System error)

W: Failed to fetch http://extras.ubuntu.com/ubuntu/dists/raring/Release.gpg  Something wicked happened resolving 'extras.ubuntu.com:http' (-11 - System error)

E: Some index files failed to download. They have been ignored, or old ones used instead.