It looks like the issue is that the Apache proxy is failing to connect to the backend server on port 8445. There are a few things you can check to troubleshoot this:
Verify that the websocket server is running and listening on port 8445. You can use the netstat command to check this:
sudo netstat -tlnp | grep 8445
If the websocket server is running, you should see a line that looks like this:
tcp 0 0 0.0.0.0:8445 0.0.0.0:* LISTEN <websocket server PID>/websocket
Verify that there are no firewalls or security groups blocking traffic to port 8445. You can check this by trying to connect to the websocket server from the server itself:
telnet localhost 8445
If the connection is successful, you should see a blank screen. If the connection is refused, there may be a firewall or security group blocking traffic.
Verify that the websocket server is configured to accept connections from the Apache proxy. Depending on the websocket server you are using, this may involve setting a specific IP address or hostname to listen on, or configuring access control lists (ACLs) to allow connections from the Apache server's IP address.
Check the logs of the websocket server to see if there are any error messages indicating why the connection is being refused.