On Fri, 22 Feb 2019 at 11:58, James Knott via talk <talk@gtalug.org> wrote:
On 02/22/2019 11:33 AM, Giles Orr wrote:
We use this ability a fair bit at my work: the web server determines what name you're looking for from the incoming header,
What would be in the header? All IP has in the header to differentiate connections is IP address and port number. For example, if I wanted to access the Mississauga Library ebook collection, I could open a browser to 13.92.99.128 and it would connect to port 443 for https. I have not provided any other information. So, how would the appropriate server be accessed from that, when multiple servers share a single IP?
Since HTTP 1.1, a request may contain the "Host" header: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Host which web servers can they use to serve proper content for a given host name. See, for example, http://nginx.org/en/docs/http/request_processing.html for information how nginx deals with multiple servers on the same IP address. For https, there is SNI: https://en.wikipedia.org/wiki/Server_Name_Indication