Component : RFC -

Solution : https://service.sap.com/sap/support/notes/52959 (SAP Service marketplace login required)

Summary :
An SAP Note indicates issues with RFC connection setups, where the RFcOpen or RfcAccept methods in RFC client and server programs return RFC_HANDLE_NULL due to unrecognized service entries like sapms, sapdpxx, and sapgwxx. The cause is linked to missing entries in the "services" file of the underlying operating system, which are critical for establishing TCP/IP connections with the SAP system. To resolve this, systems administrators must add the required service definitions (sapdp00 to sapdp99, sapgw00 to sapgw99, and sapms) into the appropriate "services" file on UNIX, NT, or AS/400 platforms, ensuring proper entry termination.

Key words :
symptom incorrect rfc connection setup, prerequisites incorrect tcp/ip configuration, sapgw99    3399/tcpsapms<sid> starts, rfc client program, sapdp99    3299/tcpsapgw00    3300/tcp, rfc server program, additional key words, affected sap gateway, <windir>/system32/drivers/, - sapms<sid> unknown

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