dns - What does binding a Rails Server to 0.0.0.0 buy you? -

I am using "www.xip.io" as a DNS wildcard for testing on different devices. I have set my primary domain to my IP address. I set fire to a railway server with the bundled excel rail server and I here www. Lt; Ip_address & gt; .xip.io: 3000 and note that my rail server does not have the answer.

However, if I bind my rail server to 0.0.0.0, such as bundle exec rails server -b 0.0.0.0 , it works! I do not understand that 0.0.0.0 is asking its server to work for it. Can anyone understand the meaning of this?

Service to bind all IP addresses . Rail server used to do this by default, but 4.2 has been changed to force only localhost . Basically if it is only bound to localhost , then it will only respond locally to localhost or 127.0.0.1 , which is a DNS service Can not work because it is not a public IP address.

When you use 0.0.0.0 it will bind the and local hosts to your local IP address.