violettec@linux:~# sudo apt-get update Ign:1 https://mirrors.ustc.edu.cn/ubuntu bionic InRelease Ign:2 https://mirrors.ustc.edu.cn/ubuntu bionic-updates InRelease Ign:3 https://mirrors.ustc.edu.cn/ubuntu bionic-backports InRelease Ign:4 https://mirrors.ustc.edu.cn/ubuntu bionic-security InRelease Ign:5 https://mirrors.ustc.edu.cn/ubuntu bionic-proposed InRelease Err:6 https://mirrors.ustc.edu.cn/ubuntu bionic Release Certificate verification failed: The certificate is NOT trusted. The certificate chain uses not yet valid certificate. Could not handshake: Error in the certificate verification. [IP: 202.141.160.110 443] Err:7 https://mirrors.ustc.edu.cn/ubuntu bionic-updates Release Certificate verification failed: The certificate is NOT trusted. The certificate chain uses not yet valid certificate. Could not handshake: Error in the certificate verification. [IP: 202.141.160.110 443] Err:8 https://mirrors.ustc.edu.cn/ubuntu bionic-backports Release Certificate verification failed: The certificate is NOT trusted. The certificate chain uses not yet valid certificate. Could not handshake: Error in the certificate verification. [IP: 202.141.160.110 443] Err:9 https://mirrors.ustc.edu.cn/ubuntu bionic-security Release Certificate verification failed: The certificate is NOT trusted. The certificate chain uses not yet valid certificate. Could not handshake: Error in the certificate verification. [IP: 202.141.160.110 443] Err:10 https://mirrors.ustc.edu.cn/ubuntu bionic-proposed Release Certificate verification failed: The certificate is NOT trusted. The certificate chain uses not yet valid certificate. Could not handshake: Error in the certificate verification. [IP: 202.141.160.110 443] Reading package lists... Done E: The repository 'https://mirrors.ustc.edu.cn/ubuntu bionic Release' does not have a Release file. N: Updating from such a repository can't be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details. E: The repository 'https://mirrors.ustc.edu.cn/ubuntu bionic-updates Release' does not have a Release file. N: Updating from such a repository can't be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details. E: The repository 'https://mirrors.ustc.edu.cn/ubuntu bionic-backports Release' does not have a Release file. N: Updating from such a repository can't be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details. E: The repository 'https://mirrors.ustc.edu.cn/ubuntu bionic-security Release' does not have a Release file. N: Updating from such a repository can't be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details. E: The repository 'https://mirrors.ustc.edu.cn/ubuntu bionic-proposed Release' does not have a Release file. N: Updating from such a repository can't be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details.
E: The repository 'https://mirrors.ustc.edu.cn/ubuntu bionic Release' does not have a Release file. N: Updating from such a repository can't be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details.
当我尝试搜索靠上点的报错时：
1
Certificate verification failed: The certificate is NOT trusted. The certificate chain uses not yet valid certificate. Could not handshake: Error in the certificate verification.
发现也许是服务器时间错误，导致证书检验错误。我看了一下服务器时间：
1 2
violettec@linux:~# date -R Sun, 28 Jan 2018 15:59:44 +0000
