[ubuntu-20.04][apt] apt update 실패 해결

그동안 무시하고 있었는데 오늘 필(?) 받아서 찾아서 해결한 결과를 기록으로 남깁니다.

1번째 증상: NO_PUBKEY

: Skipping acquire of configured file 'stable/source/Sources' as repository 'https://download.docker.com/linux/ubuntu focal InRelease' does not seem to provide it (sources.list entry misspelt?)
W: GPG 오류: http://developer.download.nvidia.com/compute/cuda/repos/ubuntu2004/x86_64  InRelease: 다음 서명들은 공개키가 없기 때문에 인증할 수 없습니다: NO_PUBKEY ABCDEFGHIJKLMNOP
E: The repository 'http://developer.download.nvidia.com/compute/cuda/repos/ubuntu2004/x86_64  InRelease' is no longer signed.

apt-key 로 키 서버에 등록해서 해결했습니다.

sr@srwiz:~$ sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys ABCDEFGHIJKLMNOP
Executing: /tmp/apt-key-gpghome.AOFUSiDnnU/gpg.1.sh --keyserver keyserver.ubuntu.com --recv-keys ABCDEFGHIJKLMNOP
gpg: key ABCDEFGHIJKLMNOP: public key "cudatools <cudatools@nvidia.com>" imported
gpg: Total number processed: 1
gpg:               imported: 1

하지만, 또 다른 오류가 숨어 있네요.

sr@srwiz:~$ sudo apt update
....
W: Skipping acquire of configured file 'stable/source/Sources' as repository 'https://download.docker.com/linux/ubuntu focal InRelease' does not seem to provide it (sources.list entry misspelt?)
W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: https://storage.googleapis.com/bazel-apt stable InRelease: 다음 서명이 올바르지 않습니다: EXPKEYSIG AAAAAAA Bazel Developer (Bazel APT repository key) <bazel-dev@googlegroups.com>
W: https://storage.googleapis.com/bazel-apt/dists/stable/InRelease 파일을 받는데 실패했습니다  다음 서명이 올바르지 않습니다: EXPKEYSIG AAAAAAA Bazel Developer (Bazel APT repository key) <bazel-dev@googlegroups.com>
W: Some index files failed to download. They have been ignored, or old ones used instead.

이번엔 gpg 키를 직접 내려 받아 apt-key 에 등록해줍시다.

sr@srwiz:~$ curl https://bazel.build/bazel-release.pub.gpg | sudo apt-key add -
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100  4714  100  4714    0     0   6344      0 --:--:-- --:--:-- --:--:--  6336
OK

사용자에 따라 또 다른 오류가 숨어 있을 수 있지만 이후 제 pc는 sudo apt update 결과가 말끔해졌습니다.

도움이 되시길 바랍니다!!