W: GPG error: http://repo.mysql.com/apt/debian bullseye InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 467B942D3A79BD29
E: The repository 'http://repo.mysql.com/apt/debian bullseye InRelease' is not 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.
找准错误提示：
The following signatures couldn’t be verified because the public key is not available
红框处 写你的报错KEY
命令是：
sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 你的KEY
然后apt update 就好了
之后直接安装sudo apt install -y mysql-server
就可以了
标签：because,debain11,apt,signatures,报错,key,mysql From： https://www.cnblogs.com/zhg1016/p/17382237.html