ISP put me behind NAT
fedilink

I’m connected via a 4G modem. Got this setup about 3 years ago. In the beginning it was enough to look for the public IP (what’s my IP). The modem showed some sort of private ip in the ui. I’m running stuff at home (Homeassistant, Gitea,) and bought a domain and pointed it to my home IP via Cloudflare. After some time I’ve noticed my modem shows the public IP also internally. For about 2 years now it ran flawlessly, the IP changed from time to time, but not really more than once in several weeks. For about a week all stopped working and the modem shows IP 100.xxxx and outside 85.something I guess I’m behind NAT now. Normal port forwarding on the modem is useless now. Is it possible to open the ports via UPNP? I’ve tried via miniupnp from my Ubuntu server, but it just throws an error.

upnpc -a ifconfig enp1s0| grep "inet addr" | cut -d : -f 2 | cut -d " " -f 1 22 22 TCP

Can I use this to somehow open the ports via UPNP on my modem and bypass the blocking? I can’t even OpenVPN to my modem anymore.

EDIT: i also run AdguardHome, that I use as Private DNS on my Android phone

UPDATE: everything except Adguard Home used as Private DND on my Android works! I’ve used this: https://github.com/mochman/Bypass_CGNAT/wiki/Oracle-Cloud-(Automatic-Installer-Script) - free Oracle VPS + automated well described script. Even HTTPS works fine!

poVoq
link
fedilink
English
41Y

If they sell an “internet connection” then selling one behind a CGNAT is a breach of contract, because it is not a connection to the internet but only a selective forwarding service from within their intranet.

Similar to how the consumer protection agencies fought against fake speed promises and hidden “fair use” volume clauses, CGNAT should also be forbidden to be advertised as “internet”.

@Schmeckinger@feddit.de
link
fedilink
English
2
edit-2
1Y

We have more internet connections than IPv4’s they can’t just pull new ones out of their ass. Also IPv6 is internet too.

poVoq
link
fedilink
English
-21Y

This is a myth. There are large swath of IPv4 address spaces totally unused and many ISPs hoard them without actually using them.

An IPv6 only internet connection would also still be miles better than CGNAT connection.

@Schmeckinger@feddit.de
link
fedilink
English
1
edit-2
1Y

How? You can literally turn IPv4 off on your whole network, or selectively by device. But if you turn off your IPv4 you will get cut off of a good chunk of the internet.

And the only reason we have unused IPv4’s is because a big part of the internet is behind NAT of some kind like CGNAT.

poVoq
link
fedilink
English
01Y

There is nothing wrong with an organization sharing an single IPv4 internally via NAT, but if your ISP sells you a connection to the internet, this by definition means you get a unique public IP address, otherwise it isn’t an internet connection.

IPv6 support could be better for sure, but it is still much better than not having an internet connection at all as in the case of a CGNAT.

@DoomBot5@lemmy.world
link
fedilink
English
01Y

No it doesn’t. It means you have access to the internet through that company’s infrastructure. You still have full access to the internet behind a CGNAT even if you can’t be reached directly from the internet.

poVoq
link
fedilink
English
0
edit-2
1Y

An internet connection by definition is two-way. The internet was designed as a network of interconnected computers. A one-way only connection like through a CGNAT is preventing you from doing a lot of things the internet was designed for.

@DoomBot5@lemmy.world
link
fedilink
English
01Y

You have a 2 way connection as facilitated by the CGNAT gateway that routes responses back to your network.

poVoq
link
fedilink
English
01Y

If you have no unique public IP there are a lot of things you can’t do, so it isn’t a true two way connection.

@Schmeckinger@feddit.de
link
fedilink
English
11Y

CGNAT usually only applies to the IPv4. The IPv6 prefix you get is usually public.

poVoq
link
fedilink
English
01Y

“Usually”? In my experience usually this is not the case. Starlink for example promised to make ipv6 available like that, but AFAIK it is still CGNAT only.

@Schmeckinger@feddit.de
link
fedilink
English
1
edit-2
1Y

I can only talk how it is in Germany, where CGNAT with a public IPv6 prefix is the norm and a public IPv4 costs extra money unless you have a legacy contract.

In addition this also depends on the ISP.

Create a post

A place to share alternatives to popular online services that can be self-hosted without giving up privacy or locking you into a service you don’t control.

Rules:

  1. Be civil: we’re here to support and learn from one another. Insults won’t be tolerated. Flame wars are frowned upon.

  2. No spam posting.

  3. Posts have to be centered around self-hosting. There are other communities for discussing hardware or home computing. If it’s not obvious why your post topic revolves around selfhosting, please include details to make it clear.

  4. Don’t duplicate the full text of your blog or github here. Just post the link for folks to click.

  5. Submission headline should match the article title (don’t cherry-pick information from the title to fit your agenda).

  6. No trolling.

Resources:

Any issues on the community? Report it using the report flag.

Questions? DM the mods!

  • 1 user online
  • 191 users / day
  • 419 users / week
  • 1.14K users / month
  • 3.85K users / 6 months
  • 1 subscriber
  • 3.71K Posts
  • 74.6K Comments
  • Modlog