Install problem: `getaddrinfo: Name or service not known`

No, you don’t need to be sorry. You actually mentioned the name of the file prior to that post within your previous post. I am sorry that I couldn’t notice it. Anyways, Thank for the reply.

However, I am still stuck with this problem, and I don’t know how can I acquire insightful information from tcpdump command of docker0, it seems that it is stuck one the gem update bundler command is tried to be executed.