问题
I have written a Windows service in C# which connects to the Firebase Database and stores data. For connection and database communication, I use a NuGet Packages called "FirebaseAuthentification.net" and "FirebaseDatabase.net", both by StepUp Labs, Inc.
On my test system, everything works fine. On the customer's system, there are firewall/procy restrictions which deny communication. We already opened Port 443 and are able to send a request, but the answer does not arrive.
Old GCM Doc says:
If your organization has a firewall that restricts the traffic to or from the Internet, you need to configure it to allow connectivity with GCM in order for your GCM client apps to receive messages. The ports to open are: 5228, 5229, and 5230. GCM typically only uses 5228, but it sometimes uses 5229 and 5230. GCM doesn't provide specific IPs, so you should allow your firewall to accept outgoing connections to all IP addresses contained in the IP blocks listed in Google's ASN of 15169.
But Messaging is not Database Authentification. I did not find anything in the firebase docs or anywhere else in the net.
Which Ports do I have to open in order to make the Connection work?
回答1:
Firebase Authentication and the Firebase Realtime Database both use HTTPS to communicate between the client and the server. This means that all communication goes over port 443.
The database communication uses web sockets over port 443 when possible. You might want to check if the firewall does something to specifically block web sockets.
来源：https://stackoverflow.com/questions/50811695/which-ports-have-to-be-open-to-communicate-with-firebase-database-not-fcm-messa