linux系统shell终端下载报错——“Ubuntu 20.04 LTS _Focal Fossa - Release amd64 (20200423)” 的盘片插入驱动器“/cdrom/”再按「回车」键

“Ubuntu 20.04 LTS _Focal Fossa - Release amd64 (20200423)” 的盘片插入驱动器“/cdrom/”再按「回车」键"

首先:cd /etc/apt
打开编辑sources.list: sudo nano source.list

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注释掉deb cdrom:开头的行

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ctrl+O写入,ctrl+X离开
然后执行命令sudo apt-get update

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