I'm pretty sure this is possible but I can't quite recall how to do it. Does it involved signing up with a service somewhere and running a cron job on a single system behind my home router?

Just to clarify, I want to map a domain name I own to my home IP address, which may change every few months. I am unable to get a static IP.

Any tips greatly appreciated. Thank you.

There are several dynamic IP DNS sites, noip.com, dynu.com or DuckDNS are a few. They typically have a client program that runs in the background to update their servers when your IP changes. Newer router models may have a built in dyndns client so you may not need to install anything on the computer itself.

The sites posted are free but using your own domain name might cost a fee.

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Thank you. I wanted to use DuckDNS, but unfortunately they require you to sign in with an account from another service, none of which I have or care to have at this point in time. So I opted for a different provider.

I've never used dynamic DNS, but this is certainly possible to do. I wrote a Python script that checks what my IP address is, and compares it to the current A record of my domain name. If it is different, it will update the A record of my domain name via CloudFlare's API. I have this script run on a cron job on a raspberry pi powered by the USB port of my modem, so I have it run periodically as well as every time my modem (and hence the pi) reboots.

This method obviously requires you to be using a DNS provider with an API. The raspberry pi part is optional. In my case, I did it that way because I know my IP address will change if my modem reboots.

I don't know if this is better than using a dynamic DNS provider, but it was easy enough to implement and hasn't failed me yet.

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I do this with all my machines. My domain registrar (Mythic Beasts, whom I'd thoroughly recommend) have an API for dynamic DNS changes which saves the hassle of trying to find external IP addresses. I've got raspberry pi-like devices running behind my routers to regularly update the IPv4 address and all my machines will update their IPv6 addresses so I can access any of my machines from anywhere else. Works a treat.

I used to run a cron job but nowadays I use a little snap I hacked together. I just install it on any new device, configure and forget about it.

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