Laravel Echo Server - Socket.io - Polling fails - laravel

Question

The Laravel Echo Server is launched via:
laravel-echo-server start and is running fine:
L A R A V E L E C H O S E R V E R
version 1.3.1
Starting server...
✔ Running at localhost on port 6001
✔ Channels are ready.
✔ Listening for http events...
✔ Listening for redis events...
Server ready!
CHANNEL private-user:09222583-ef73-5640-bcc8-062b36c4f380.d3d0a4d2-0c95-5f5f-aea4-1dfe1fa36483
However, in the front-end, the polling seems to fail. The Network tab shows that requests keep trying to connnect and fail:
The URLs look like this:
https://example.com:6001/socket.io/?EIO=3&transport=polling&t=MGEIXhf
The laravel-echo-server.json looks like this:
{
"authHost": "https://example.com",
"authEndpoint": "/broadcasting/auth",
"clients": [],
"database": "redis",
"databaseConfig": {
"redis": {
"host": "127.0.0.1",
"password": "56df4h5dfg4"
}
},
"devMode": false,
"host": null,
"port": "6001",
"protocol": "https",
"socketio": {},
"sslCertPath": "/etc/nginx/ssl/example_com/ssl-bundle.crt",
"sslKeyPath": "/etc/nginx/ssl/example_com/example_com.key",
"sslCertChainPath": "",
"sslPassphrase": ""
}
The port 6001 seems to be open in the ufw:
Status: active
To Action From
-- ------ ----
...
6001 ALLOW Anywhere
...
6001 (v6) ALLOW Anywhere (v6)
...

Answer 1

Verify that you used same port number in js file also.
import Echo from 'laravel-echo'
window.io = require('socket.io-client');
window.Echo = new Echo({
broadcaster: 'socket.io',
host: window.location.hostname + ':6001'});

Answer 2

I was having the exact same problem. On my local setup everything worked fine but on the staging, droplet ufw was blocking every incoming request /var/log/ufw.log showed them all being blocked. I already had 6001 open in ufw, and I'd even given my IP access to everything in ufw, but requests were still blocked.
Although I really didn't want the security risk, I briefly disabled ufw and everything started working, connections were made instantly, no timeouts. I then quickly enabled ufw again, and everything continued working. I tested new connections in other browsers - all working.
So although it's really bad advice to try turning the firewall off and on again, it did work for me.
I hope someone else might chime in with a way to diagnose and fix such UFW issues in a secure way.

Answer 3

I got to the cause of the problem in my situation.
The first rule I'd set up with ufw was to allow ssh traffic.
I then installed fail2ban and part of that process saved the iptables using iptables-persistent.
When I later added a ufw rule to allow 6001 everything was working.
After a reboot 6001 stopped being open even though it was listed as open in ufw's status output - the reason it wasn't working was the iptables had been restored with the copy taken before the 6001 rule was added.
So if you've got iptables-persistent running make sure you use
sudo dpkg-reconfigure iptables-persistent
after adding any new ufw rules.