Debian 12 CD-ROM 源修改为网络源
一台机器安装Debian时选择了CD-ROM作为更新源，apt-get 时提示如下错误：
Please use apt-cdrom to make this CD-ROM recognized by APT. apt-get update cannot be used to add new CD-ROMs
一、编辑文件
nano /etc/apt/sources.list
二、加#注释掉CDROM 那行源
#cdrom://[Debian GNU/Linux 12.1.0 _Bookworm_ - Official amd64 DVD
三、添加官方源
deb http://deb.debian.org/debian/ bookworm main contrib non-free deb http://deb.debian.org/debian/ bookworm-updates main contrib non-free deb http://security.debian.org/debian-security bookworm-security main contrib non-free
四、更新即可
apt-get update apt-get dist-upgrade apt-get upgrade