Obtaining address lists from the rpcbind server

RPC binding protocol V4 provides a procedure, RPCBPROC_GETADDRLIST, for obtaining a list of addresses supported by a service. When a client queries the z/OS® rpcbind server using the UDP protocol over IPV4 or IPV6 transport, the rpcbind server confines the reply to fit within one UDP IPv4 datagram. To obtain all addresses supported by the service, the client should use TCP protocol when invoking the RPCBPROC_GETADDRLIST procedure. For more information on RPC binding protocol V4 and the RPCBPROC_GETADDRLIST procedure, see RFC 1833. See Related protocol specifications for information on accessing RFCs.

Result: Your client might not be able to reach every address returned by the RPCBPROC_GETADDRLIST procedure and possibly might not be able to reach the service at all with the information provided by the RPCBPROC_GETADDRLIST procedure. Following are some examples:

The service might register a specific address that is not reachable from the client.
If you use UDP to query the rpcbind server, the addresses returned within the span of a single datagram might be unreachable by the client.

Restriction: If the service supports private network addresses, rpcbind returns those addresses in an RPCBPROC_GETADDRLIST reply. If your client is in the private network with the service, your client can use these addresses to contact the service. However, if the service and the client are in different private networks, unpredictable results will occur. See RFC 1918 for more information about private network addresses. See Related protocol specifications for information on accessing RFCs.