我刚刚在之前运行 Ubuntu 19.04 的笔记本电脑上安装了 Ubuntu 20.04。使用了完整的“擦除磁盘并安装 Ubuntu”选项，安装介质是 U 盘。
安装后我尝试做的第一件事当然是sudo apt-get updatebam！错误：
Err:6 http://security.ubuntu.com/ubuntu focal-security/main i386 Packages
Hash Sum mismatch
Hashes of expected file:
- Filesize:145444 [weak]
- SHA256:441dab3c8a255fd5fec066a31c406525dab6a5629029e426170033835738ef0f
- SHA1:70e9e8dec8b9f753d2ddb0d8696b2714fcdbd2b0 [weak]
- MD5Sum:04ce44602d56d586cc827d4dae28de89 [weak]
Hashes of received file:
- SHA256:925ddfd0bf7dc54656ebd729304c8826c779229eab489e39cbda3b83498c305d
- SHA1:9de08f4ffa54879375ef93899b8179785e795f9a [weak]
- MD5Sum:3782b8853b62334b19cd0db4e2c4840b [weak]
- Filesize:145444 [weak]
Last modification reported: Thu, 29 Oct 2020 19:16:50 +0000
Release file created at: Sat, 31 Oct 2020 04:53:35 +0000
Fetched 252 kB in 3s (93.9 kB/s)
Reading package lists... Done
E: Failed to fetch http://security.ubuntu.com/ubuntu/dists/focal-security/main/binary-i386/by-hash/SHA256/441dab3c8a255fd5fec066a31c406525dab6a5629029e426170033835738ef0f Hash Sum mismatch
Hashes of expected file:
- Filesize:145444 [weak]
- SHA256:441dab3c8a255fd5fec066a31c406525dab6a5629029e426170033835738ef0f
- SHA1:70e9e8dec8b9f753d2ddb0d8696b2714fcdbd2b0 [weak]
- MD5Sum:04ce44602d56d586cc827d4dae28de89 [weak]
Hashes of received file:
- SHA256:925ddfd0bf7dc54656ebd729304c8826c779229eab489e39cbda3b83498c305d
- SHA1:9de08f4ffa54879375ef93899b8179785e795f9a [weak]
- MD5Sum:3782b8853b62334b19cd0db4e2c4840b [weak]
- Filesize:145444 [weak]
Last modification reported: Thu, 29 Oct 2020 19:16:50 +0000
Release file created at: Sat, 31 Oct 2020 04:53:35 +0000
E: Some index files failed to download. They have been ignored, or old ones used instead.
另外，由于未满足依赖关系，我无法安装 gnome-tweak-tools 但我猜那是因为更新不起作用。我已经看到其他几个用户报告了同样的问题，但是那里建议的解决方案（比如删除 apt 列表目录的内容）要么对我不起作用，要么不适用于我的情况。这应该是一个 LTS 稳定版本，但最基本的功能失败了。
那么，有没有不需要我绞尽脑汁的解决方案呢？