WireGuard Peer-Config not accepted in GUI when Endpoint is a FQDN insted a IP-Adress – Opal | GL-SFT1200

[Flash_what]

Device & Firmware Info:

• Model: GL‑iNet GL‑SFT1200 (Opal)
• OpenWrt base: 18.06
• Kernel: 4.14.90
• GL.iNet Firmware: 4.3.25

Problem: WireGuard peer config fails to save when using FQDN as endpoint.
When configuring a WireGuard peer in the Web UI, using a FQDN (e.g. example.com:51820) as the endpoint fails immediately during save.

• Error message:
  "An unknown error occurred. Please check your network environment or restart the device."
• The error occurs before any connection attempt is made.
• It also happens when the router has no internet connection, so this is not a DNS resolution issue.

How to Reproduce
Open the Web UI and create a new WireGuard peer.

Enter a FQDN in the Endpoint Host field (e.g. example.com:51820).

Click “Apply” or “Save”.

An error immediately appears, and the config is not saved.

Replace the FQDN with a static IP → Save works successfully.

Expected Behavior
Saving a peer config with a FQDN as endpoint should work as it does with an IP.

The field should accept both hostnames and IP addresses.

Internally, endpoint_host should be stored correctly.

Actual Behavior
The Web UI seems to reject FQDNs and only allows IPs.

Saving the config fails even before trying to establish a VPN connection.

Is there a known workaround?

[bruce]

Hi,

My teammate has tested this in the GL GUI, on the Opal with v4.3.25, the peer endpoint is domain (FQDN), it did not reproduce.

May I know the "endpoint" content is copied/pasted directly or keyboard by hand? How to reproduce the issue?

[Flash_what]

Thank you very much for your reply.
I have now discovered that the hyphen in the URL seems to be the problem (for-example.com:51820).
When I remove it as a test, the GUI accepts the URL. Unfortunately, encoding the hyphen with ‘%2D’ does not work either.
Can anyone help me solve this problem?

[9b9e69c2-4b75-4420]

It looks like you've discovered a bug. @bruce , could you ask the GL devs if they know Bobby Tables?

Try encapsulating with ', ie: 'for-example.com:51820' or 'for-example.com':51820. The appropriate conf would be found at ll /etc/config/wireguard*. This is just speculation.

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[Flash_what]

Thank you very much for pointing out that I could simply change the configuration directly via SSH to bypass the frontend bug (?). As a long-time hobby Linux user and home lab enthusiast, I should have thought of that myself. It works now!

[bruce]

Hi,

Thank you for your feedback.

We have reproduced this issue and submitted to R&D for further debugging and improve it.