Is there a reasonable way of having a the server on a shelf in my house that people can ping via an IP addrees?
Yes. See below. I assume by "ping" you really mean "contact using a web-browser" in order to receive an HTTP response code 418.
What are the words I use to google for the solution to this problem?
- "static ip-address"
- "port forwarding"
- "DHCP reservation"
UK SOHO Broadband
Home broadband is typically provided through a router that uses network address translation (NAT) where the internal network uses a private address range (e.g. 192.168.1.) and the external "public" address is dynamically allocated by the Internet Service Provider (ISP). Because it is dynamically allocated, it can change from time to time.
Usually, when your home computers are turned on they broadcast a DHCP request asking for an internal IP-address they can use. Usually your router responds and allocates an address from a pool of internal addresses.
The internal addresses typically can't be reached directly but your router uses NAT to translate between internal and external addresses.
You need to ask for a "static IP-address". This means iyour public IP address will be fixed and can be published for use with your teapot. You won't get to choose the actual address.
Some UK ISPs charge an extra monthly fee for this (e.g. BT) but some do not (e.g. Zen).
Teapot Internal Address
Your Teapot might have a configurable fixed IP-address, in which case you should configure an address within the internal network range used by your router but outside the range handed out by your router - it's DHCP range.
Alternatively you can configure your router to always give the teapot the same internal address.
Incoming requests to your router, for teapot service, need to be passed on to the specific internal address of your teapot. You do this using "port forwarding". Some routers may refer to this as "pinholes" or use some other terminalogy.