Direct answer

Carrier-grade NAT (CGNAT) means your ISP shares a public IPv4 address among subscribers. Ordinary home-router port forwarding may not be enough for outsiders to reach your server.

Recommended procedure

  1. Compare your router WAN/Internet IPv4 address with the public IPv4 seen from an outside network.
  2. If the router shows a private or shared-range address, ask your ISP whether a public IPv4 address or port-forwarding service is available.
  3. Consider properly secured IPv6 connectivity, an outbound tunnel or a game-hosting provider when public inbound IPv4 is unavailable.
  4. Only after obtaining a routable address should you configure router forwarding and host firewalls.

Why this matters

DNS records only turn names into addresses. They cannot bypass CGNAT or create an inbound mapping through your ISP. A local Minecraft connection proves only that the game process is reachable from the local network.

How to verify the result

Test the Minecraft TCP port from a completely external network while the server is running. A successful internal LAN test does not validate public accessibility.

Version and compatibility notes

The 100.64.0.0/10 shared address range commonly signals CGNAT; multiple-router double NAT is a separate problem that can coexist.

Official references

These sources were checked for the current MSH revision. Version-sensitive details should always be confirmed against the project documentation for the release you run.

Was this article helpful?
Help us improve this article

Tell us what is missing, unclear, outdated, or incorrect. You can also suggest something we should add.

What could we improve?
Do not include passwords, server IPs, or other private information.0 / 1000