Ubuntu安装docker报错：E: Package 'containerd.io' has no installation candidate

Ubuntu版本：19.10

按照docker官网的安装方法，在Ubuntu上按装docker时报错：

Package containerd.io is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source
E: Package 'containerd.io' has no installation candidate

原因是执行命令

$ sudo add-apt-repository \
   "deb [arch=amd64] https://download.docker.com/linux/ubuntu \
   $(lsb_release -cs) \
   stable"

其中：$(lsb_release -cs)返回的“eoan”即Ubuntu 19.10。猜测可能是Ubuntu 19.10的问题，替换为表示ubuntu 18.10的“bionic”，如下：

$ sudo add-apt-repository \
   "deb [arch=amd64] https://download.docker.com/linux/ubuntu \
   bionic \
   stable"

为了避免冲突，记得修改“/etc/apt/sources.list”，注释掉

deb-src [arch=amd64] https://download.docker.com/linux/ubuntu eoan stable