Floating IP challenge
from alzymologist@sopuli.xyz to selfhosted@lemmy.world on 27 Apr 08:53
https://sopuli.xyz/post/44771411

Ok, I’ll share the ultimate guerilla-selfhosting challenge I can’t figure out yet: what if my internet connection is G5 prepaid sim card in the middle of the woods (it actually is)? Apparently, I do have IPv6 more or less stable (undocumented), but that’s kind of limiting at times. Seems barely possible, but!

The homebrewserver.club/low-tech-website-howto.html#n… states:

The fiber connection itself is not necessary, especially if you keep your data footprint small, but a fixed IP adress is very handy.

which kind of implies someone figured out a way to get around it. Would someone share the trick?

#selfhosted

threaded - newest

CameronDev@programming.dev on 27 Apr 08:57 next collapse

DNS is the way around it. But, the caveat is that while you can update your DNS entry as often as you like, itll often be cached on intermediate servers for an unknown amount of time. Expect a downtime of anywhere from a few minutes to days everytime your address changes.

alzymologist@sopuli.xyz on 27 Apr 09:02 collapse

So how does this work then, I host DNS and it pushes my data to other DNS servers around the net every time my IP address changes? Can you share an example of how could be set up?

poVoq@slrpnk.net on 27 Apr 09:10 next collapse

No, typically you use the DNS server of the domain provider.

Hosting your own DNS server is possible, but if you don’t have a static IP address the other DNS servers will have no idea which server to ask when your IP changes, so in this specific scenario it wouldn’t work. And in general it isn’t really worth it as you get a DNS server with your domain included.

surewhynotlem@lemmy.world on 27 Apr 11:01 collapse

You run a dynamic DNS script. It reaches out to the DNS server (provided by whoever registers your domain name) every five minutes and says “my IP is x.x.x.x”.

The problem is that it takes a few minutes to update when it changes. That might not fit your use case.

bruce965@lemmy.ml on 27 Apr 09:05 next collapse

Assuming you are not in a CGNAT, which is common for mobile networks: DNS with low TTL such as FreeDNS, pointing to your IP. And ofc, if you have a router in between, port-forwarding.

Otherwise, a VPN such as Tailscale. But you would need to install it on all your devices.

Otherwise, for HTTP(S) web services, a reverse-proxy such as CloudFlare.

alzymologist@sopuli.xyz on 27 Apr 09:33 collapse

Whoa, FreeDNS is a killer, I wish I knew about it before! I have domains to donate probably (unless they expired lol). I sure need to try that.

poVoq@slrpnk.net on 27 Apr 09:06 next collapse

DynDNS short for dynamic DNS is what you want. But IPv6 only websites are unfortunately even in 2026 still not accessible by many people due to their ISP only supporting IPv4.

Natanael@slrpnk.net on 27 Apr 09:40 collapse

Probably reverse proxy too if it’s really unstable

zeitverschreib@freundica.de on 27 Apr 09:15 next collapse

@alzymologist

I tested a 5G connection as failover for a few weeks.

My homeserver connected to a very small VPS, routing traffic through Wireguard. So the public IPv4/v6 remained constant, even when the gateway switched between WAN connections.

alzymologist@sopuli.xyz on 27 Apr 09:28 collapse

Yeah, using VPS to route traffic is an obvious solution, I’m thinking about it as the last resort here.

Decronym@lemmy.decronym.xyz on 27 Apr 09:20 next collapse

Acronyms, initialisms, abbreviations, contractions, and other phrases which expand to something larger, that I’ve seen in this thread:

Fewer Letters More Letters
CGNAT Carrier-Grade NAT
DNS Domain Name Service/System
HTTP Hypertext Transfer Protocol, the Web
IP Internet Protocol
NAT Network Address Translation
VPN Virtual Private Network
VPS Virtual Private Server (opposed to shared hosting)

[Thread #258 for this comm, first seen 27th Apr 2026, 09:20] [FAQ] [Full list] [Contact] [Source code]

lemming741@fedinsfw.app on 27 Apr 10:17 next collapse

I have a $5/mo VPS that my domain points to. It runs caddy reverse proxy to my homelab over wireguard. If my home IP changes, the wireguard ‘server’ has the the IP of the VPS wg ‘client’ configured as the Endpoint, with no endpoint set on the VPS. It will switch over pretty quick.

https://anders94.medium.com/wireguard-config-for-the-initiated-2b1cc5f2b1ee

https://forum.netgate.com/topic/188527/roaming-peer-fails

qaz@lemmy.world on 27 Apr 11:46 next collapse

Assuming reliability is the priority I would suggest going with Tailscale Funnels or a cheap VPS acting as intermediary.

I don’t have a lot of experience with dealing with GCNAT, but perhaps you could look into some solution with UPnP or RFC 6887.

bluGill@fedia.io on 27 Apr 11:46 collapse

When IPv6 was first created, the dream was that your machine would get a new IP address any time the whole network felt some need for that. The idea was, as someone added a network, we may need to change the way your systems are numbered in order to make the backbone routing a lot easier to fit in memory. This hasn't seemed to work out, but that was the dream.