只安裝安全更新
sudo unattended-upgrade
自动安裝安全更新
sudo dpkg-reconfigure -plow unattended-upgrades
设置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
