Connectivity Requirements for RDP Licensing Server Connectivity and Firewall Rules

If you deploy an RDP License on a VM in Azure, then that VM needs to be able to talk to the RDP Licensing Server. The RDP License allows multiple users to log into the VM at the same time. By default, only 2 users can log into the VM concurrently. RDP License lets you increase that number based on the license. This is a typical use case for a Jump box VM deployment in Microsoft Azure.

For the RDP license to work, it needs to validate with the RDP Licensing Server. For this, the Firewall needs to allow communication. To be able to allow this communication, you need to know the following:

1. The IP address of the VM where the RDP license is configured
2. The IP address of the RDP Licensing Server
3. The port numbers and the protocol on which to allow the communication

The port numbers on which the communication occurs are as below:

1. TCP on port number 135. This is the main port where communication occurs.
2. TCP on 49152–65535 i.e. RPC dynamic address range. A dynamic port is assigned from this range for validation-related communication.

Using this information ensure that the Firewall in your environment is configured appropriately to allow communication.