apt-get -s dist-upgrade | grep "^Inst" | grep -i securi | awk -F " " {'print $2'} | xargs apt-get install

只安裝安全更新
sudo unattended-upgrade

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自動安裝安全更新
sudo dpkg-reconfigure -plow unattended-upgrades

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讓 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