LLMVision automation can’t fetch image via DuckDNS (works when run manually)

Hey all,

I’m having trouble getting LLMVision working properly with Home Assistant and could use a second pair of eyes.

Setup:

• Home Assistant, Frigate, and Ollama all running on separate Proxmox instances
• DuckDNS + Let’s Encrypt for external access
• OPNsense with split DNS configured

What works:

• Running llmvision.image_analyzer directly in Home Assistant works perfectly every time

What doesn’t work:

• When I trigger an automation that sends an event to Ollama, it breaks
• I’ve tried multiple blueprints, but no luck

What I’m seeing:

• Logs show custom_components.llmvision.media_handlers trying to download the image via my external URL
• The fetch fails, even though:
  • The DuckDNS domain works fine externally (tested from laptop + phone)
  • Certificates are valid
  • Split DNS is configured correctly

Extra context:

• Claude (via MCP server) suggested CoreDNS in HA might be bypassing internal DNS and resolving via Cloudflare
• I haven’t found much solid info confirming that, and I’m not sure if it’s a dead end

Question:
Has anyone run into something similar with LLMVision / HA / DuckDNS setups?
Any ideas why HA can’t fetch its own externally exposed URL during automations, even though everything works manually?

Thanks! 🙏