element cannot connect to home server

[StephenJose-Dai]

Steps to reproduce

I deployed synapse and made nginx proxy. I used nginx to reverse proxy synapse's http 8008, and nginx's external proxy is 9998. When I entered my server address in the windows application, let's say it is https://abc.com:9998, it told me that this does not look like a matrix server, but my mobile phone can connect to it normally. I am sure there is no problem with the URL. I tried to update the let's certificate to zerossl, unfortunately to no avail. I don't know how to solve this problem. I hope to get help, please!

If I use http directly it can connect normally, because it does not go through nginx, but directly connects to synapse's port 8008. I don't believe it is my nginx problem, this is my nginx configuration.

It is worth noting that my domain name only resolves IPV6, and I believe element supports ipv6 access

Outcome

I deployed synapse and made nginx proxy. I used nginx to reverse proxy synapse's http 8008, and nginx's external proxy is 9998. When I entered my server address in the windows application, let's say it is https://abc.com:9998, it told me that this does not look like a matrix server, but my mobile phone can connect to it normally. I am sure there is no problem with the URL. I tried to update the let's certificate to zerossl, unfortunately to no avail. I don't know how to solve this problem. I hope to get help, please!

If I use http directly it can connect normally, because it does not go through nginx, but directly connects to synapse's port 8008. I don't believe it is my nginx problem, this is my nginx configuration.

It is worth noting that my domain name only resolves IPV6, and I believe element supports ipv6 access！

Operating system

Windows

Application version

1.11.86.0

How did you install the app?

https://element.io/download

Homeserver

synapse

Will you send logs?

Yes

[t3chguy]

Will you send logs?
Yes

Not seeing any logs from you, those would say which request fails and why you cannot connect

[StephenJose-Dai]

Will you send logs?
Yes

Not seeing any logs from you, those would say which request fails and why you cannot connect

I'm not sure what kind of log you need, nginx or Element log?

[StephenJose-Dai]

Will you send logs?
Yes

Not seeing any logs from you, those would say which request fails and why you cannot connect

I'm not sure what kind of log you need, nginx or Element log?

This is my nginx access log, it looks normal

I don't see any entries in my nginx error log, which I think is a good sign.

This is the log of my synapse container. I don't see any problem.

[t3chguy]

Element logs are the only helpful ones here. Ctrl shift I to open the console.

[StephenJose-Dai]

Element logs are the only helpful ones here. Ctrl shift I to open the console.

I think this is what you want

[t3chguy]

I suggest reading through your 2nd screenshot, looks like your CORS/ACAO is invalid

[StephenJose-Dai]

I suggest reading through your 2nd screenshot, looks like your CORS/ACAO is invalid

I believe you have seen my nginx configuration. It seems that there is no configuration for this. The nginx configuration given in the official documentation is like this.
So according to the error, should I configure the corresponding cross-domain parameters in nginx?

[t3chguy]

The header may be being sent by your nginx, any other reverse proxy before it, your Synapse, anything, one thing it isn't being sent by is your Element.

Seems like the header value got doubled up which makes it invalid.

[StephenJose-Dai]

The header may be being sent by your nginx, any other reverse proxy before it, your Synapse, anything, one thing it isn't being sent by is your Element.

I solved this problem. It seems that synapse will automatically add this

"add_header Access-Control-Allow-Origin "*" always;"

But I didn't know, so I added this sentence to nginx and caused a conflict. I just need to comment out

"add_header Access-Control-Allow-Origin "*" always;"

in nginx.

[t3chguy]

Its in the Matrix Spec https://spec.matrix.org/v1.12/client-server-api/#web-browser-clients so its fairly implied that a Matrix Server would send it. Did that fix the issue for you now then?

[StephenJose-Dai]

Its in the Matrix Spec https://spec.matrix.org/v1.12/client-server-api/#web-browser-clients so its fairly implied that a Matrix Server would send it. Did that fix the issue for you now then?

My problem has been solved, and I thank you very much for your suggestions and help.