• 只安装安全更新

sudo unattended-upgrade

• 自动安裝安全更新

sudo dpkg-reconfigure -plow unattended-upgrades

• 让 apt-get upgrade 只安裝安全更新

sudo vi /etc/apt/preferences

Package: *
Pin: release a=lucid-security
Pin-Priority: 500

Package: *
Pin: release o=Ubuntu
Pin-Priority: 50

sudo apt-get update

sudo apt-get upgrade

参考：互联网