The new error:

ENETUNREACH 198.18.0.18:443

It means the add-on cannot reach the target network at all (network unreachable) from the HA server, which is different from the previous Firebase error. This usually indicates the VPN/proxy is not applied to the Home Assistant add-on container itself, even if it works on your phone or NAS.

Key point:

The Zircon3D add-on runs inside a Docker container, and:
It does NOT automatically use your system/NAS VPN or proxy
Environment proxy variables often don’t work unless the container is explicitly configured to route traffic through it

What likely happened
Your VPN works on your device
But the HA add-on container is still using the normal network
So requests to zircon3d.com (and Firebase) fail or get routed to invalid IPs like 198.18.x.x

Recommended solution

Run Home Assistant through a system-level VPN:

Install VPN on your router, or
Install VPN directly on the Home Assistant host machine

This ensures all containers (including Zircon3D) can access the internet properly.

Also, just to confirm, are you located in China?
Currently, Zircon3D relies on Google Firebase services, which are restricted in China. Because of this, Zircon3D is not well supported in China at the moment due to network limitations.

Sorry about this, we understand it’s inconvenient and are considering alternative solutions for better regional support in the future.

2026-03-25 09:22:04 error Failed to make session -> {"error":{"message":"connect ENETUNREACH 198.18.0.18:443","name":"Error","stack":"Error: connect ENETUNREACH 198.18.0.18:443\n at AxiosError.from (/app/node_modules/axios/dist/node/axios.cjs:962:24)\n at RedirectableRequest.handleRequestError (/app/node_modules/axios/dist/node/axios.cjs:3794:29)\n at RedirectableRequest.emit (node:events:508:28)\n at eventHandlers.<computed> (/app/node_modules/follow-redirects/index.js:49:24)\n at ClientRequest.emit (node:events:508:28)\n at emitErrorEvent (node:_http_client:108:11)\n at TLSSocket.socketErrorListener (node:_http_client:575:5)\n at TLSSocket.emit (node:events:508:28)\n at emitErrorNT (node:internal/streams/destroy:170:8)\n at emitErrorCloseNT (node:internal/streams/destroy:129:3)\n at Axios.request (/app/node_modules/axios/dist/node/axios.cjs:5110:41)\n at process.processTicksAndRejections (node:internal/process/task_queues:104:5)\n at async ZirconSession._getFirebaseOptions (/app/proxy/server/proxy-core/zircon-client/zircon-session.js:48:19)\n at async ZirconSession.init (/app/proxy/server/proxy-core/zircon-client/zircon-session.js:58:33)\n at async ZirconClient.makeSession (/app/proxy/server/proxy-core/zircon-client/zircon-client.js:64:17)\n at async ZirconClient.signIn (/app/proxy/server/proxy-core/zircon-client/zircon-client.js:36:25)\n at async /app/proxy/routes/proxy/use-proxy.js:177:13","config":{"transitional":{"silentJSONParsing":true,"forcedJSONParsing":true,"clarifyTimeoutError":false,"legacyInterceptorReqResOrdering":true},"adapter":["xhr","http","fetch"],"transformRequest":[null],"transformResponse":[null],"timeout":0,"xsrfCookieName":"XSRF-TOKEN","xsrfHeaderName":"X-XSRF-TOKEN","maxContentLength":-1,"maxBodyLength":-1,"env":{},"headers":{"Accept":"application/json, text/plain, /","User-Agent":"axios/1.13.6","Accept-Encoding":"gzip, compress, deflate, br"},"httpsAgent":null,"method":"get","url":"https://zircon3d.com/static/page.json","allowAbsoluteUrls":true},"code":"ENETUNREACH"}}

auth/network-request-failed (fetch failed)

Zircon3D currently requires access to Google Firebase for login/session initialization, even though the rest of the system runs locally.

Possible solutions:
1. Use a network that can access Google services (VPN or similar)
2. Configure your router or system to allow outbound access to Firebase/Google APIs
3. If you already have a VPN on your network, make sure the Home Assistant machine (not just your phone/PC) is also using it

Notes:
• This issue is not related to your Home Assistant setup, your logs show HA connection is working fine
• It’s purely a network restriction to Firebase

2026-03-25 09:32:26 info Connecting to database -> {"path":"/data/zircon-v3.db"}

2026-03-25 09:32:26 info Initializing database with default data if necessary

2026-03-25 09:32:26 info Connecting to ha -> {"url":"http://192.168.123.237:8123/api/websocket"}

(node:1) ExperimentalWarning: SQLite is an experimental feature and might change at any time

(Use node --trace-warnings ... to show where the warning was created)

2026-03-25 09:32:39 error Failed to make session -> {"error":{"code":"auth/network-request-failed","customData":{"message":"TypeError: fetch failed","appName":"[DEFAULT]"},"name":"FirebaseError"}}

2026-03-25 09:32:39 info Proxy server has started -> {"port":11200,"host":"0.0.0.0"}

this is the dialog.