Ubuntu 20.04.6升级LTS时do-release-upgrade移除官方源导致失败的问题求助

阿华AIGC实验室

2026-4-22

大家好，我最近在把一台运行Ubuntu 20.04.6的服务器升级到最新LTS版本时卡壳了，遇到一个非常棘手的问题：do-release-upgrade工具会自动移除apt源列表里的官方Ubuntu源，之后就因为找不到必要的升级包而终止流程，我完全搞不懂它为什么要这么做，来这里求助各位！

先给大家展示下我的当前环境：

当前的有效APT源配置

我执行了以下命令查看/etc/apt/sources.list里的有效配置（过滤掉空行和注释）：

:~# cat /etc/apt/sources.list | grep -v ^$ | grep -v ^#

deb http://ftp.ubuntu.com/ubuntu focal main restricted

deb http://ftp.ubuntu.com/ubuntu focal-updates main restricted

deb http://ftp.ubuntu.com/ubuntu focal universe

deb http://ftp.ubuntu.com/ubuntu focal-updates universe

deb http://ftp.ubuntu.com/ubuntu focal multiverse

deb http://ftp.ubuntu.com/ubuntu focal-updates multiverse

deb http://ftp.ubuntu.com/ubuntu focal-backports main restricted universe multiverse

deb http://security.ubuntu.com/ubuntu focal-security main restricted

deb http://security.ubuntu.com/ubuntu focal-security universe

deb http://security.ubuntu.com/ubuntu focal-security multiverse

APT更新正常执行

运行apt update后，所有源都能正常获取，没有报错，输出如下：

:~# apt update

Hit:1 http://ppa.launchpad.net/ondrej/apache2/ubuntu focal InRelease

Hit:2 http://ftp.ubuntu.com/ubuntu focal InRelease

Get:3 http://ftp.ubuntu.com/ubuntu focal-updates InRelease [114 kB]

Get:4 http://ftp.ubuntu.com/ubuntu focal-backports InRelease [108 kB]

Get:5 http://security.ubuntu.com/ubuntu focal-security InRelease [114 kB]

Hit:6 https://esm.ubuntu.com/apps/ubuntu focal-apps-security InRelease

Hit:7 https://esm.ubuntu.com/apps/ubuntu focal-apps-updates InRelease

Hit:8 https://esm.ubuntu.com/infra/ubuntu focal-infra-security InRelease

Hit:9 https://esm.ubuntu.com/infra/ubuntu focal-infra-updates InRelease

Fetched 336 kB in 3s (104 kB/s)

Reading package lists... Done

Building dependency tree

Reading state information... Done

All packages are up to date.

另外，我的/etc/apt/sources.list.d目录下还有几个额外的源文件，主要是ESM相关的仓库。

执行`do-release-upgrade`后的错误流程

当我运行do-release-upgrade时，一开始的包管理器检查是正常的，然后它提示：

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]

我按下回车后，工具开始获取Jammy（22.04）的源，但奇怪的是，它只保留了security.ubuntu.com和ESM的源，把所有ftp.ubuntu.com的官方源都移除了！最后直接报错：

Get:1 http://security.ubuntu.com/ubuntu jammy-security InRelease [110 kB]
Get:2 https://esm.ubuntu.com/apps/ubuntu jammy-apps-security InRelease [7,553 B]
Get:3 https://esm.ubuntu.com/apps/ubuntu jammy-apps-updates InRelease [7,459 B]
Get:4 https://esm.ubuntu.com/infra/ubuntu jammy-infra-security InRelease [7,453 B]
Get:5 https://esm.ubuntu.com/infra/ubuntu jammy-infra-updates InRelease [7,452 B]
Get:6 http://security.ubuntu.com/ubuntu jammy-security/main i386 Packages [277 kB]
Get:7 http://security.ubuntu.com/ubuntu jammy-security/main amd64 Packages [631 kB]
Get:8 https://esm.ubuntu.com/apps/ubuntu jammy-apps-security/main amd64 Packages [41.5 kB]
Get:9 http://security.ubuntu.com/ubuntu jammy-security/main Translation-en [148 kB]
Get:10 http://security.ubuntu.com/ubuntu jammy-security/main amd64 c-n-f Metadata [11.0 kB]
Get:11 http://security.ubuntu.com/ubuntu jammy-security/restricted i386 Packages [29.7 kB]
Get:12 http://security.ubuntu.com/ubuntu jammy-security/restricted amd64 Packages [651 kB]
Get:13 http://security.ubuntu.com/ubuntu jammy-security/restricted Translation-en [104 kB]
Get:14 http://security.ubuntu.com/ubuntu jammy-security/restricted amd64 c-n-f Metadata [532 B]
Get:15 http://security.ubuntu.com/ubuntu jammy-security/universe amd64 Packages [756 kB]
Get:16 https://esm.ubuntu.com/apps/ubuntu jammy-apps-security/main i386 Packages [32.7 kB]
Get:17 http://security.ubuntu.com/ubuntu jammy-security/universe i386 Packages [544 kB]
Get:18 http://security.ubuntu.com/ubuntu jammy-security/universe Translation-en [136 kB]
Get:19 https://esm.ubuntu.com/apps/ubuntu jammy-apps-updates/main amd64 Packages [479 B]
Get:20 http://security.ubuntu.com/ubuntu jammy-security/universe amd64 c-n-f Metadata [15.9 kB]
Get:21 http://security.ubuntu.com/ubuntu jammy-security/multiverse amd64 Packages [36.5 kB]
Get:22 http://security.ubuntu.com/ubuntu jammy-security/multiverse i386 Packages [1,032 B]
Get:23 http://security.ubuntu.com/ubuntu jammy-security/multiverse Translation-en [7,060 B]
Get:24 http://security.ubuntu.com/ubuntu jammy-security/multiverse amd64 c-n-f Metadata [260 B]
Get:25 https://esm.ubuntu.com/infra/ubuntu jammy-infra-security/main amd64 Packages [479 B]
Get:26 https://esm.ubuntu.com/infra/ubuntu jammy-infra-updates/main amd64 Packages [479 B]
Fetched 3,567 kB 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.