Service was running fine for months and is running into WebSocket error all of a sudden.

⚠️ Please verify that this bug has NOT been raised before.

• I checked and didn’t find similar issue

🛡️ Security Policy

• I agree to have read this project Security Policy

📝 Describe your problem

My site has been up and running fine for months, but I recently noticed that I am running into the Websockets error again.

Cannot connect to the socket server. [Error: timeout] Reconnecting...
Using a Reverse Proxy? Check how to config it for WebSocket

I did make the changes required for nginx back when installing for the first time and didn’t make any changes to the nginx config since, at least I can’t remember. I just now copied the nginx settings from your link just in case, but no change I am afraid. Here’s what I’m running with:

server {
    server_name  status.mydomain.de;

    location / {
      proxy_set_header   X-Real-IP $remote_addr;
      proxy_set_header   X-Forwarded-For $proxy_add_x_forwarded_for;
      proxy_pass         http://localhost:3001/;
      proxy_http_version 1.1;
      proxy_set_header   Upgrade $http_upgrade;
      proxy_set_header   Connection "upgrade";
    }

    listen 443 ssl; # managed by Certbot
    ssl_certificate /etc/letsencrypt/live/status.mydomain.de/fullchain.pem; # managed by Certbot
    ssl_certificate_key /etc/letsencrypt/live/status.mydomain.de/privkey.pem; # managed by Certbot
    include /etc/letsencrypt/options-ssl-nginx.conf; # managed by Certbot
    ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem; # managed by Certbot

}

server {
    if ($host = status.mydomain.de) {
        return 301 https://$host$request_uri;
    } # managed by Certbot

    server_name  status.mydomain.de;
    listen 80;
    return 404; # managed by Certbot
}

Nothing in the nginx error log, nothing outstanding in the access log. Tried different browsers

Is there anything else which might block Websockets?

Environment:

• Docker

cat docker-compose.yml
version: '2.3'

services:
  uptime-app:
    container_name: uptime-app
    image: louislam/uptime-kuma:1
    restart: always
    volumes:
      - ./data:/app/data
    ports:
      - 3001:3001

🐻 Uptime-Kuma Version

Latest docker image

💻 Operating System and Arch

Ubuntu 20.04.4 LTS x86_64

🌐 Browser

Chromium, Firefox

🐋 Docker Version

Docker version 20.10.14, build a224086

🟩 NodeJS Version

Not that I know

[zell-mbc]

Good find, that TLS 1.3 sounds promising, I’ll definitely check this out and will report back! Coincidentally I am running Mattermost on a different server, so this is good to know anyway.

Edit: It doesn’t seem to be related to TLS 1.3 unfortunately. I turned it off and still can’t get through. In case someone wants to try as well, here’s what I did:

1. Comment out v1.3 in /etc/letsencrypt/options-ssl-nginx.conf (ssl_protocols TLSv1.2; # TLSv1.3;)
2. Restart nginx
3. Check that 1.3 is indeed off, curl -I -v --tlsv1.3 --tls-max 1.3 https://yourdomain
4. Test your site

Edit2: I moved things over to a free Oracle Cloud Ubuntu instance, using Traefik instead of nginx. All up and running again, unfortunately this also means I can’t troubleshoot the original instance any longer -> Hence I need to close the case.

By the way, it looks to me that the free virtual server Oracle offers fits Uptime-Kuma well, as often one will want to monitor “outside in” but not spend money on firing up a dedicated VM with a different provider.

[louislam]

It may be a nginx issue. https://github.com/mattermost/mattermost-mobile/issues/4557