Even with the experience of building ss, the building of ssr is not as smooth as I imagined. I guessed that it may be a mistake in using the command or the influence of ss, which has caused it to fail. In addition, the vps is extremely unstable, so I am ready to restart. Then apply for a better configuration of $10 per month.
It is much easier to build a vps again. This time it is the centOS operating system, but it is almost the same. The main thing is the ssr build command. This time it is a simple version, just two steps:
1. yum install wget -y
2.wget --no-check-certificate https://freed.ga/github/shadowsocksR.sh; bash shadowsocksR.sh
However, it is not the reason of ss and ssr, but the interception of the vps provider or the campus network. The console in the background cannot log in. It is better to buy an ss account directly.