dnsdomain-nameip
On a local machine I can map my machine IP address with some domain like below:
127.0.0.1 testwebsite.com
My question is once I get a domain name (say testwebsite.com) from a domain name provider, can I say to them "map it to my machine IP address where my web application is deployed" or does it have to be deployed on their environment?
Also, do I have to provide this mapping at the time of the domain registration or can it be done later as well?
Most webservers can be run as reverse proxies, suitable for doing this. If you do everything right, you'll end up with something like the below (minus the "remote" part - since this will all be on one machine):
127.0.0.1:80)127.0.0.1:59873)You can use a lightweight webserver like nginx (even runs on Windows), configure it to reverse proxy test.com to 127.0.0.1:59873 and then add the following entry to your HOSTS file:
127.0.0.1 test.com
What you are after are called "glue records".
A glue record is the IP address of a name server held at the Domain Name registry.
Glue records are required when you wish to set the name servers of a domain name to a hostname under the domain name itself.
For example if you wished to set the name servers of example.com to ns1.example.com and ns2.example.com you would need to also provide the glue records (i.e. the IP addresses) for ns1.example.com and ns2.example.com.
If you did not provide the glue records for these name servers then your domain name would not work as anyone requiring DNS information for it would get stuck in a loop:
What is the name server for example.com? -> ns1.example.com What is the IP address of ns1.example.com? -> don't know, try looking at name server for example.com What is the name server for example.com? -> ns1.example.com
...and so on.
With the glue record in place the registry will hold the IP address and the loop will not occur:
What is the name server for example.com? -> ns1.example.com What is the IP address of ns1.example.com? -> [IP Address]
Best Answer
A domain such as example.com has various records, such as the A record and MX records.
These records redirect traffic to a location. Where that location is doesn't matter.
If you setup the A record for example.com to point to your public IP address (the ip address provided by your ISP) then anyone who enters example.com can find its route to your modem.
It is then up to your modem to tell the traffic where to go next. If your modem is not also a router, the modem will simply redirect everything to the router behind it. The router then needs to have a port mapping that tells where the traffic needs to go to.
Given that websites use HTTP traffic, which by default is set to port 80, you need to forward port 80 to the local ip address where the webserver is located. If you host the webserver on your own computer, then you setup port 80 to the ip address of your local computer.
That said, this will continue to work until your IP address changes. If that happens you need to update your domain's A record to point to the new IP address. There are services that allow you to do this for you, but bringing your own domain is often a premium feature. In addition, using your own webserver at home means that you will lose internet speed.
If these problems are something you want to avoid, it is probably going to be cheaper to get a cheap webhosting. Most of the time, they include a free domain too.
That said, to answer your questions:
You can map it to anything, including your own ip address, as long as you have control of DNS records (this is something you need to make sure, in case you go for webhosting + domain. If you only go for a domain, it is always going to provide DNS management.)
No, you do not have to provide this mapping at the time of the registration. Until you do, the domain will simply not forward or more likely forward to the website of the registration party. You can change it at any time if you please to whatever you want. Keep in mind that changing DNS takes time. You change it instantly at the location of the provider, but other DNS servers must then query and update the records. Given that there are over a million of DNS servers all around the world, it can take up to an hour before the changes are processed in your contry, and up to 48 hours until it is done all over the world.