LineageOS 下载页无法在中国大陆访问的细节 | Details of the case that LineageOS download page is unable to be accessed in mainland China

English Translation follows Chinese.

最近我们注意到了一些中国大陆的中国用户无法访问 LineageOS 的下载页面 https://download.lineageos.org/ ，目前我已就此事展开调查。

目前，我正在联系各关联方。具体细节将在此页公布。

1. Linode: 回复如下（有删减，原文请见下方的英文翻译）：

我至少可以向您确认，我们对任何类型的网站和数据中心都不进行任何类型的过滤。我们是一个不干涉的基础设施提供商，所以除非有法律强制要求，我们一般不参与监管内容或网站。

从中国到世界其他地区，听到有关连通性问题的消息并不罕见。

虽然我不能确定，你所提供的第一条 MTR 信息显示你已经连接到了网关路由，但是接受的 Linode 可能丢掉了这些请求：

14 307 ms * 309 ms 173.230.159.7

2. 正在联系 LineageOS

初步判断，IP 被墙掉。可能原理：单向拦截目标 IP 的返回数据

traceroute --tcp --port=443 download.lineageos.org

解决方案：

使用中国大陆建立的镜像：

1. 清华大学：https://mirrors.tuna.tsinghua.edu.cn/lineage-rom/full/

2. 中科大：https://mirrors.ustc.edu.cn/lineageos/

Traceroute 数据：

北京电信：

Recently, we noticed some users in mainland China can access to LineageOS download page ( https://download.lineageos.org/ ). Now, I’m taking into an investigation.

Now, I’m contacting relevant parties. Details of the case that LineageOS download page is unable to be accessed in mainland China will be released at this site.

1. Linode Reply

I can at least confirm to you that we perform no filtering of any type whatsoever to websites to and from our datacenters. We’re a hands-off infrastructure provider so we generally don’t take part in policing content/sites except when we’re legally compelled.

I can say that it’s not uncommon to hear about connectivity issues from China to the rest of the world. This is because the government performs extensive filtering of foreign traffic so they can block content that they deem unacceptable.

https://en.wikipedia.org/wiki/Great_Firewall

Though I honestly can’t be certain on this. The first MTR you provided shows that your traffic is at least reaching a gateway router, but the receiving Linode might be dropping it:

14 307 ms * 309 ms 173.230.159.7

2. Contacting LineageOS

Probably, the IP is banned by the Great Firewall of China. Possible Principle: the One-way return of the target IP data block.

traceroute --tcp --port=443 download.lineageos.org

Solution：

Use mirrors set us in China:

1. Tsinghua University：https://mirrors.tuna.tsinghua.edu.cn/lineage-rom/full/

2. University of Science and Technology：https://mirrors.ustc.edu.cn/lineageos/

Traceroute Data: