报错信息

W: GPG error: http://mirrors.aliyun.com/docker-ce/linux/ubuntu focal InRelease: The following signatures couldn’t be verified because the public key is not available: NO_PUBKEY 7EA0A9C3F273FCD8
E: The repository ‘http://mirrors.aliyun.com/docker-ce/linux/ubuntu focal 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.
root@VM-16-14-ubuntu:/# sudo apt install docker-ce docker-ce-cli containerd.io

解决方案

sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 7EA0A9C3F273FCD8