Socket.IO keeps reconnecting Websocket on Cloudflare - node.js

I have a Node/Express app on server dedicated to sockets and on the client it's Angular 1.5. Running the code locally on http using the same architecture e.g. separate socket server it all works perfectly fine.
When I run the code locally it creates one connection and does very little polling via xhr. On cloudflare with https it does a lot of polling, reconnects continually and not all the messages seem to be getting to the web client
messages hit cloudflare which then redirects them to a loadbalancer running haproxy which then routes the requests to an app running in a docker instance on another machine.

Your Issue is most likely occuring beacause of an issue with cloudflare only allowing traffic to a limited set of ports. Try one of the ports listed in the below link for your server and try connecting to it.
https://support.cloudflare.com/hc/en-us/articles/200169156-Which-ports-will-Cloudflare-work-with-

After a lot of investigation I found the issue to be down to the config in haproxy. I needed to alter the timeouts around the socket routing.
This was nothing to do with ports not being open on cloudflare.
The following link helped me
http://blog.haproxy.com/2012/11/07/websockets-load-balancing-with-haproxy/

Related

Recently having trouble with socket.io connections via a Digitalocean load balancer (400 Error)

I have a DO Load Balancer that has 4 servers behind it, I've been using socket.io with Sticky Sessions enabled in the Load Balancer settings and it had been working just fine for a while.
Recently clients have not been able to connect at all getting a 400 error immediately on connection. I haven't changed anything in the way I connect to the sockets at all. If I do require that the transport be 'websocket' only from the client it does connect successfully, but then I lose out on the polling backup (one of the main benefits of socket.io).
Also, connecting directly to one of the droplets works as expected, so the issue definitely stands with the Load Balancer.
Does anyone have any idea as to any kind of set up that should be in place for this to work with the DO Load Balancers? Anything that might have changed recently?
I'm running socket.io on a NodeJS server with Express if that helps at all.
Edit #1: Added a screenshot of the LB Settings

socket.io client can't upgrade from XHR long polling to websocket

We have a server which do implement socket.io in NodeJS on Heroku.
We have a bunch of clients (Raspberry pi's) destributed on different networks across our country. They do implement socket.io clients in a NodeJS application.
It do work very well on 17/18 devices. We do have one device which are not able to upgrade the socket.io connection from a long-polling type to an actual websocket.
I cannot find the reason why.
Our server is setup with the following options:
Server settings
This is what the logs on our heroku server tells about the connection with the problematic client:
Heroku logs
As all clients are setup exactly the same way, i do not actually suspect any problems on the raspberries themselves.
Could it be a network problem where this one client is located?
- Behind the router, blocking some port etc?
Hope you have some suggestions to what the problem could be.
You tell if you need anymore information.

WebSocket over SSL: Cloudflare

I have a website behind cloudflare. I need to enable websockets over SSL without turning off cloudflare support. I have a PRO plan and hence won't get the new websocket support. I am using Nginx to proxy a SSL connection to a web socket running on a node server. Now, I read somewhere that cloudflare could work with approved ports would support websockets. Hence, I'm using 8443 for the Nginx port and another port for the node server. Using wscat it returns a 200 error.
$ wscat -c wss://xyz.com:8443
error: Error: unexpected server response (200)
I know that the websocket is expecting a 101 code. However, if I visit https://xyz.com:8443, I can see the page displayed by the node server telling me proxy is working. Also, once I turn off cloudflare support, the websocket starts working. Any clues to get this working. I know I can create a subdomain but I'd prefer running the websocket behind cloudflare.
If you're trying to access this through CloudFlare's network you'd need to explicitly have web sockets enabled on your domain before they will work -- regardless of the port. As in, even if the port can pass through our network, that won't automatically mean that web sockets will be enabled or accessible on your domain.
You can try contacting our support team to request an exception to see if they can enable it for your domain, but typically this is still only available at the business and enterprise levels.
Disclaimer: I work at CloudFlare.

Socket.io - invalid HTTP status code on SOME browsers

Just after a few weeks of working fine, our Socket.io started spewing errors on some browsers. I've tried updated to the latest Socket.io version, I've tried our setup on different machines, I've tried all sorts of machines, it seems to work on most browsers with no clear pattern of which work.
These errors appear on a second interval:
OPTIONS https://website.com/socket.io/?EIO=2&transport=polling&t=1409760272713-52&sid=Dkp1cq0lpKV75IO8AdA3 socket.io-1.0.6.js:2
XMLHttpRequest cannot load https://website.com/socket.io/?EIO=2&transport=polling&t=1409760272713-52&sid=Dkp1cq0lpKV75IO8AdA3. Invalid HTTP status code 400
We're behind Amazon's ELB, Socket.io on polling because the ELB router doesn't support WebSockets.
I found the problem that has been causing this, and it's is really unexpected...
This problem comes from using load balanced services like AWS ELB (independent EC2 should be fine though) and Heroku, their infrastructure doesn't support Socket.io features fully. AWS ELB flat out won't support WebSockets, and Heroku's router is trash for Socket.io, even in conjunction with socket.io-redis.
The problem is hidden when you use a single server, but as soon you start clustering, you will get issues. A single Heroku dyno on my application worked fine, and then the problems started appearing in production out of development, when we weren't using more than one server. We tried on ELB with sticky-load balance and even then, we still had the same issues.
When socket.io returns 400 errors, in this case it was saying "This session doesn't exist and you never completed the handshake", because you completed the handshake on a different server in your cluster.
The solution for me was just dedicating an EC2 instance for my web app to handle Socket.io.

Socket.io on port 80

I've made a node application which listens on port 80, my application works fine on localhost, but when I run it on my VPS, I get a different log and a different result ( websockets just don't work )
A comparison between localhost's log and VPS' log:
Node's log on localhost
Node's log on VPS
As you see, in VPS, xhr is used instead of websocket after it says "info: transport end (socket end)"
I don't use any web server on my VPS and I ran my application as root.
Are you running a web server in front of your node app on your VPS? If so, make sure it is new enough and properly configured to do websockets. For instance, on modern Ubuntu the stock nginx is not new enough yet to support web sockets, so you have to install a separate package to get websocket support.
2nd guess: is there a proxy server between your browser and your VPS?
Have you run it as the super user on the VPS? Normal users are typically blocked from opening ports below 1024.
Our server hosted on VPS, using port 80. The io connection fired through cellular data and through WIFI fine, but in some wifi networks it didn't.
So we had used different port, then it works.

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