如何将 Ubuntu 16.04 升级到 18.04？
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答案1
升级 Ubuntu，请按照以下步骤操作
步骤 1：更新 UBUNTU 16.04 服务器
在升级到 Ubuntu 18.04 之前，您应该先更新当前的 16.04。建议在升级之前更新/升级所有已安装的软件包。要更新 Ubuntu，请连接到服务器并运行以下命令：
sudo apt update && sudo apt dist-upgrade && sudo apt autoremove
步骤 2：安装 UBUNTU 更新管理器
更新 Ubuntu 16.04 服务器后，如果尚未安装，请运行以下命令来安装 update-manager-core。
sudo apt-get install update-manager-core
然后打开 update-manager 配置文件，并确保提示行设置为 lts
sudo nano /etc/update-manager/release-upgrades
确认提示符等于 lts
# Default behavior for the release upgrader.
[DEFAULT]
# Default prompting behavior, valid options:
#
# never - Never check for a new release.
# normal - Check to see if a new release is available. If more than one new
# release is found, the release upgrader will attempt to upgrade to
# the release that immediately succeeds the currently-running
# release.
# lts - Check to see if a new LTS release is available. The upgrader
# will attempt to upgrade to the first LTS release available after
# the currently-running one. Note that this option should not be
# used if the currently-running release is not itself an LTS
# release, since in that case the upgrader won't be able to
# determine if a newer release is available.
Prompt=lts
如果不是，请将其更改为 lts 并保存文件。
步骤 3：执行 UBUNTU 18.04 LTS 升级
现在您的系统已准备就绪，请运行以下命令开始将 Ubuntu 升级到最新开发版本。
sudo do-release-upgrade -d
按照屏幕上的说明进行操作... y = 是且 N = 否。当系统提示您是否希望升级时，请输入 y 以表示是。
Do you want to start the upgrade?
1 installed package is no longer supported by Canonical. You can
still get support from the community.
2 packages are going to be removed. 64 new packages are going to be
installed. 394 packages are going to be upgraded.
You have to download a total of 234 M. This download will take about
1 minute with your connection.
Installing the upgrade can take several hours. Once the download has
finished, the process cannot be canceled.
Continue [yN] Details [d] y
等待所有较新的软件包下载…这可能需要一段时间，具体取决于您的互联网连接速度。下载完所有软件包后，您的系统将立即开始升级……
新软件包安装完成后，系统会询问您是否要删除过时的软件包。在此处输入 y。如果您有自定义的系统，您可能希望输入 d 来查看列表……以防万一您需要重新安装。
Remove obsolete packages?
53 packages are going to be removed.
Continue [yN] Details [d]y
等待该过程完成，重启完成..您将收到重启通知。
Restart required
To finish the upgrade, a restart is required.
If you select 'y' the system will be restarted.
Continue [yN] y
当一切设置正确后，您的系统应该升级到最新的 Ubuntu 版本。
欢迎使用 Ubuntu 18.04 LTS（GNU/Linux 4.15.0-19-generic x86_64）
答案2
我已从 16.04 安全地升级到 18.04，以下是我所做的：
编辑 repo 文件：
sudo nano /etc/apt/sources.list
将代号替换为您要升级到的实际代号：
如果你使用 nano^\作为快捷方式，因为我是从 16.04 开始的，所以我将单词替换xenial为bionic
保存文件。
然后让 Ubuntu 知道这个变化：
sudo apt update
然后进行升级：
sudo apt dist-upgrade
然后，如果您愿意，您可以只让 3 个内核版本通过：
sudo apt autoremove
答案3
什么都没用。在尝试了建议的解决方案后，我最终手动下载了软件包，将它们复制到 /var/cache/apt/archives 中，并从 /var/cache/apt/archives/partial 中删除了损坏的软件包。