无法升级Ubuntu服务器19.04至19.10 (“ubuntu-极小”无法定位)

Question

$ sudo do-release-upgrade
Checking for a new Ubuntu release
Get:1 Upgrade tool signature [1,554 B]
Get:2 Upgrade tool [1,319 kB]
Fetched 1,320 kB in 0s (0 B/s)
authenticate 'eoan.tar.gz' against 'eoan.tar.gz.gpg'
extracting 'eoan.tar.gz'

Reading cache

Checking package manager
Reading package lists... Done
Building dependency tree
Reading state information... Done
Hit http://asi-fs-n.contabo.net/ubuntu disco InRelease
Hit http://asi-fs-n.contabo.net/ubuntu disco-updates InRelease
Hit http://asi-fs-n.contabo.net/ubuntu disco-backports InRelease
Hit http://security.ubuntu.com/ubuntu disco-security InRelease
Hit http://ppa.launchpad.net/certbot/certbot/ubuntu disco InRelease
Hit http://archive.ubuntu.com/ubuntu disco InRelease
Hit http://repo.mysql.com/apt/ubuntu disco InRelease
Ign http://ppa.launchpad.net/deadsnakes/ppa/ubuntu disco InRelease
Hit http://ppa.launchpad.net/ondrej/php/ubuntu disco InRelease
Err http://ppa.launchpad.net/deadsnakes/ppa/ubuntu disco Release
  404  Not Found [IP: 91.189.95.83 80]
Fetched 0 B in 0s (0 B/s)
Reading package lists... Done
Building dependency tree
Reading state information... Done

Updating repository information

Third party sources disabled

Some third party entries in your sources.list were disabled. You can
re-enable them after the upgrade with the 'software-properties' tool
or your package manager.

To continue please press [ENTER]

Hit http://archive.ubuntu.com/ubuntu eoan InRelease
Hit http://security.ubuntu.com/ubuntu eoan-security InRelease
Fetched 0 B in 0s (0 B/s)

Checking package manager
Reading package lists... Done
Building dependency tree
Reading state information... Done

Invalid package information

After updating your package information, the essential package
'ubuntu-minimal' could not be located. This may be because you have
no official mirrors listed in your software sources, or because of
excessive load on the mirror you are using. See /etc/apt/sources.list
for the current list of configured software sources.
In the case of an overloaded mirror, you may want to try the upgrade
again later.


Restoring original system state

Aborting

Answer 1

你在使用不支持的Ubuntu临时版本。

编辑/etc/apt/sources.list文件并添加以下行：

deb http://old-releases.ubuntu.com/ubuntu disco main restricted
deb http://old-releases.ubuntu.com/ubuntu disco-updates main restricted
deb http://old-releases.ubuntu.com/ubuntu disco-security main restricted

移除不起作用的线。

然后再运行：sudo apt-get update。

并再次尝试进行发行版升级：sudo do-release-upgrade。

资料来源：如何:修复Ubuntu 19.04中的apt更新.