It's not a prober problem. I tried a simple `curl -v https://mirrors.bfsu.edu.cn/ubuntu/dists/kinetic/InRelease` via the relevant HTTPS proxy from one of our non-production machines and it never returned a response.
It's not a prober problem. I tried a simple `curl -v https:/ /mirrors. bfsu.edu. cn/ubuntu/ dists/kinetic/ InRelease` via the relevant HTTPS proxy from one of our non-production machines and it never returned a response.