Subdomains and DNS
If you are a licensed radio amateur may request a subdomain based on your call sign. If you wish to create a subdomain that is not based on your call sign you can still request it, however it is unlikely it will be approved unless you provide some really good justification.
If requesting a subdomain based on your call sign, you must verify your call sign first. You can do this by selecting "Call signs" from the "Account" menu. Once on that page click the "Verify" button next to the call sign you wish to verify. If there is no "Verify" button visible you have already verified your call sign.
Let's say your call sign is A1BCD so you verify your call sign and get issued the subdomain a1bcd.ampr.org you then request some address space and are assigned the subnet 44.128.252.0/28
You now setup a web server on IP address: 44.128.252.2
Now, you want to add some DNS records to your subdomain so other users know how to find you. So you go to your subdomain ("My subdomains" in the "DNS" menu) and you select the "Resource Records" icon under the "Actions" heading and click/tap the "Add a resource record" button.
Next you select type A (Address record) and click/tap the "Next" button.
On the next page you will note the title is: "Create resource record for a1bcd.ampr.org" and you are asked to enter the hostname. You hover your mouse over the ? help icon and see that it says that the hostname must not be fully qualified, so what does this mean?
Well, the FQDN will of course be: "www.a1bcd.ampr.org" however, as we are entering records under "a1bcd.ampr.org" we don't need to enter that part of the FQDN, so we just enter "www" in the hostname field and the system will ensure that it becomes fully qualified by tagging on "a1bcd.ampr.org" before it is stored in the database.
You fill the rest of the form in by leaving the "TTL" field empty (so it gets assigned a default value) and you enter "44.128.252.2" in the IPv4 Address field. Finally you click/tap the "Create" button. You will then be shown all resource records under your subdomain which will include the new A record for your web server.