You can find a comprehensive list of server ports that are used in Windows and major Microsoft products in the article Service overview and network port requirements for Windows. When you can specify a dedicated server port, you know what traffic flows between the hosts across the firewall, and you can define what traffic is allowed in a more directed manner.Īs a server port, please choose a port outside of the range you may want to specify below. Many RPC servers in Windows let you specify the server port in custom configuration items such as registry entries. RPC dynamic port allocation will instruct the RPC program to use a particular random port in the range configured for TCP and UDP, based on the implementation of the operating system used.Ĭustomers using firewalls may want to control which ports RPC is using so that their firewall router can be configured to forward only these Transmission Control Protocol (UDP and TCP) ports. Remote Procedure Call (RPC) dynamic port allocation is used by server applications and remote administration applications such as Dynamic Host Configuration Protocol (DHCP) Manager, Windows Internet Name Service (WINS) Manager, and so on.
RPC ports can be given from a specific range as well. How the connection worksĬlient A wants to execute some functions or wants to make use of a service running on the remote server, will first establish the connection with the Remote Server by doing a three-way handshake.
This is the payload, the important part.Ī lot of the above information is used in troubleshooting, the most important is the Dynamic RPC port number you get while talking to EPM. Stub data – the information given to functions and data exchanged between the client and server.Port – the communication endpoints for the client and server applications.If neither knows, your application vendor must tell you. It’s just a hexadecimal number, but a good network analyzer will translate the function for you. Opnum – the identifier of a function that the client wants the server to execute.
The UUID is what you use to see a specific kind of RPC application conversation, as there are likely to be many.
Endpoint mapper – a service listening on the server, which guides client apps to server apps by port and UUID.There are a few important terms to understand: This is a commonly encountered error message in the networking world and one can lose hope very fast without trying to understand much, as to what is happening ‘under the hood’.īefore getting in to troubleshooting the *RPC server unavailable- error, let’s first understand basics about the error. The following image is an example of an RPC error. You might encounter an RPC server unavailable error when connecting to Windows Management Instrumentation (WMI), SQL Server, during a remote connection, or for some Microsoft Management Console (MMC) snap-ins.