123@123-System-Product-Name:~$ sudo apt update
獲取:1 http://cn.archive.ubuntu.com/ubuntu bionic InRelease [1,122 B]
錯誤:1 http://cn.archive.ubuntu.com/ubuntu bionic InRelease
明文簽署文件不可用,結果爲‘NOSPLIT’(您的網絡需要認證嗎?)
獲取:2 http://security.ubuntu.com/ubuntu bionic-security InRelease [88.7 kB]
獲取:3 http://cn.archive.ubuntu.com/ubuntu bionic-updates InRelease [88.7 kB]
獲取:4 http://cn.archive.ubuntu.com/ubuntu bionic-backports InRelease [74.6 kB]
獲取:5 https://packages.lunarg.com/vulkan/1.2.131 bionic InRelease [6,554 B]
獲取:6 https://packages.lunarg.com/vulkan/1.2.131 bionic/main Sources [96.5 kB]
獲取:7 https://packages.lunarg.com/vulkan/1.2.131 bionic/main amd64 Packages [123 kB]
獲取:8 https://packages.lunarg.com/vulkan/1.2.131 bionic/main i386 Packages [26.8 kB]
正在讀取軟件包列表... 完成
E: 無法下載 http://cn.archive.ubuntu.com/ubuntu/dists/bionic/InRelease 明文簽署文件不可用,結果爲‘NOSPLIT’(您的網絡需要認證嗎?)
E: 倉庫 “http://cn.archive.ubuntu.com/ubuntu bionic InRelease” 沒有數字簽名。
N: 無法安全地用該源進行更新,所以默認禁用該源。
N: 參見 apt-secure(8) 手冊以瞭解倉庫創建和用戶配置方面的細節。
有時候會出現這種情況,需要更換下源,一般中科大的源好使:
123@123-System-Product-Name:/etc/apt$ sudo cp sources.list sources.list.save
[sudo] 123 的密碼:
123@123-System-Product-Name:/etc/apt$ sudo gedit source.list
在打開的文檔中把原來官方源替換爲中科大的源,我們這裏是ubuntu18.04,bionic爲版本代號,對應的源爲:
deb https://mirrors.ustc.edu.cn/ubuntu/ bionic main restricted universe multiverse
deb https://mirrors.ustc.edu.cn/ubuntu/ bionic-updates main restricted universe multiverse
deb https://mirrors.ustc.edu.cn/ubuntu/ bionic-backports main restricted universe multiverse
deb https://mirrors.ustc.edu.cn/ubuntu/ bionic-security main restricted universe multiverse
deb https://mirrors.ustc.edu.cn/ubuntu/ bionic-proposed main restricted universe multiverse
deb-src https://mirrors.ustc.edu.cn/ubuntu/ bionic main restricted universe multiverse
deb-src https://mirrors.ustc.edu.cn/ubuntu/ bionic-updates main restricted universe multiverse
deb-src https://mirrors.ustc.edu.cn/ubuntu/ bionic-backports main restricted universe multiverse
deb-src https://mirrors.ustc.edu.cn/ubuntu/ bionic-security main restricted universe multiverse
deb-src https://mirrors.ustc.edu.cn/ubuntu/ bionic-proposed main restricted universe multiverse
保存退出,再執行sudo apt update,ok。