Work‑Around Needed for “Internal or Reserved IP‑Address” Error in Nextcloud‑AIO Setup

[Sebby]

Hello everyone,

I’m currently installing Nextcloud‑AIO on a server with a special network topology. The server cannot communicate with itself via its public IP address access works only through localhost or the internal LAN IP. From the outside, however, the connection to the public IP works normally. Additionally, the intermediate network gateway makes hairpin‑NAT impossible.

During the setup the following error appears:

Error: internal or reserved ip‑address

How can this problem be worked around?

Thank you in advance.

[jtr]

The local approach with IP DNS overrides might be one possible approach: all-in-one/local-instance.md at main · nextcloud/all-in-one · GitHub

[Sebby]

An FQDN and a valid certificate are available. The problem is that when the web server tries to access itself via the public IP, the connection is routed via the LAN network. This leads to the error and the Nextcloud container does not start.

[adelaar]

For me it looks like the typical problems caused by DNS-Rebind-Protection, what is by default active on many Home User Routers.

If so, you shall deactivate it or create a rule exception for your Nextcloud‑AIO Server.

Detailed infos you will find in Manual of your Router or its support-forum.