Ubuntu 20.04.4 LTS
请参阅下面的错误。我无法再更新我的存储库或安装新软件包。每个存储库都说它不再签名。这种情况昨天才开始发生，早上它还在运行，因为我总是在早上寻找更新。当我需要安装应用程序时我注意到了这个问题并开始收到这些错误。
更新：
sudo apt update
Err:1 http://apt.postgresql.org/pub/repos/apt focal-pgdg InRelease
400 Bad Request [IP: 217.196.149.55 80]
Err:2 http://archive.ubuntu.com/ubuntu focal InRelease
400 Bad Request [IP: 91.189.91.39 80]
Err:3 http://archive.ubuntu.com/ubuntu focal-updates InRelease
400 Bad Request [IP: 91.189.91.39 80]
Err:4 http://archive.ubuntu.com/ubuntu focal-backports InRelease
400 Bad Request [IP: 91.189.91.39 80]
Err:5 http://security.ubuntu.com/ubuntu focal-security InRelease
400 Bad Request [IP: 91.189.91.38 80]
Reading package lists... Done
N: See apt-secure(8) manpage for repository creation and user configuration details.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
E: The repository 'http://apt.postgresql.org/pub/repos/apt focal-pgdg InRelease' is no longer signed.
E: Failed to fetch http://apt.postgresql.org/pub/repos/apt/dists/focal-pgdg/InRelease 400 Bad Request [IP: 217.196.149.55 80]
N: See apt-secure(8) manpage for repository creation and user configuration details.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
E: The repository 'http://archive.ubuntu.com/ubuntu focal InRelease' is no longer signed.
E: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/focal/InRelease 400 Bad Request [IP: 91.189.91.39 80]
N: See apt-secure(8) manpage for repository creation and user configuration details.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
E: The repository 'http://archive.ubuntu.com/ubuntu focal-updates InRelease' is no longer signed.
E: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/focal-updates/InRelease 400 Bad Request [IP: 91.189.91.39 80]
E: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/focal-backports/InRelease 400 Bad Request [IP: 91.189.91.39 80]
E: The repository 'http://archive.ubuntu.com/ubuntu focal-backports InRelease' is no longer signed.
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: Failed to fetch http://security.ubuntu.com/ubuntu/dists/focal-security/InRelease 400 Bad Request [IP: 91.189.91.38 80]
E: The repository 'http://security.ubuntu.com/ubuntu focal-security InRelease' is no longer signed.
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.
安装：
sudo apt install lynx
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following additional packages will be installed:
libidn11 lynx-common
The following NEW packages will be installed:
libidn11 lynx lynx-common
0 upgraded, 3 newly installed, 0 to remove and 0 not upgraded.
Need to get 1586 kB of archives.
After this operation, 5731 kB of additional disk space will be used.
Do you want to continue? [Y/n] y
Err:1 http://archive.ubuntu.com/ubuntu focal/main amd64 libidn11 amd64 1.33-2.2ubuntu2
400 Bad Request [IP: 91.189.91.38 80]
Ign:2 http://archive.ubuntu.com/ubuntu focal/universe amd64 lynx-common all 2.9.0dev.5-1
Err:3 http://archive.ubuntu.com/ubuntu focal/universe amd64 lynx amd64 2.9.0dev.5-1
400 Bad Request [IP: 91.189.91.38 80]
Err:2 http://archive.ubuntu.com/ubuntu focal/universe amd64 lynx-common all 2.9.0dev.5-1
400 Bad Request [IP: 91.189.91.38 80]
E: Failed to fetch http://archive.ubuntu.com/ubuntu/pool/main/libi/libidn/libidn11_1.33-2.2ubuntu2_amd64.deb 400 Bad Request [IP: 91.189.91.38 80]
E: Failed to fetch http://archive.ubuntu.com/ubuntu/pool/universe/l/lynx/lynx-common_2.9.0dev.5-1_all.deb 400 Bad Request [IP: 91.189.91.38 80]
E: Failed to fetch http://archive.ubuntu.com/ubuntu/pool/universe/l/lynx/lynx_2.9.0dev.5-1_amd64.deb 400 Bad Request [IP: 91.189.91.38 80]
E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing?
update和都install出现400 Bad Request错误，update显示 repo 不再签名。据我所知，Ubuntu 20.04 仍然受支持，并且应该会持续到 2025 年（如果算上 ESM，则为 2030 年）。
编辑：
根据评论，可能是时间或代理的问题。周末回来后一切都恢复正常。可能是 NTP 服务器的时间不对。如果有人遇到这个问题，我会检查你的时间并禁用所有代理。