Kubenetes - apt update GPG EXPKEYSIG error

今天執行 apt update 時出現一個錯誤：

Get:7 https://prod-cdn.packages.k8s.io/repositories/isv:/kubernetes:/core:/stable:/v1.29/deb  InRelease [1,189 B]
Err:7 https://prod-cdn.packages.k8s.io/repositories/isv:/kubernetes:/core:/stable:/v1.29/deb  InRelease
  The following signatures were invalid: EXPKEYSIG 234654DA9A296436 isv:kubernetes OBS Project <isv:kubernetes@build.opensuse.org>

W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: https://prod-cdn.packages.k8s.io/repositories/isv:/kubernetes:/core:/stable:/v1.29/deb  InRelease: The following signatures were invalid: EXPKEYSIG 234654DA9A296436 isv:kubernetes OBS Project <isv:kubernetes@build.opensuse.org>
W: Failed to fetch https://pkgs.k8s.io/core:/stable:/v1.29/deb/InRelease  The following signatures were invalid: EXPKEYSIG 234654DA9A296436 isv:kubernetes OBS Project <isv:kubernetes@build.opensuse.org>
W: Some index files failed to download. They have been ignored, or old ones used instead.

看來是 Kubenetes APT 倉庫（Repository）的 Key 換掉了。找到一篇相關的討論。

參考 Install using native package management 的指令碼的步驟2：

curl -fsSL https://pkgs.k8s.io/core:/stable:/v1.31/deb/Release.key | sudo gpg --dearmor -o /etc/apt/keyrings/kubernetes-apt-keyring.gpg
sudo chmod 644 /etc/apt/keyrings/kubernetes-apt-keyring.gpg

不用理版本號，雖然我們的 Kubenetes APT 倉庫是 v1.29 而 Key 的指令碼是 v1.31。使用上不會有任何問題。更新 Key 後 apt update 就能正常更新資訊檔了。