Step 5 — Create the RFC Connection in SAP
Step 5 — Create the RFC Connection in SAP
This guide shows how to set up the TCP/IP RFC destination that Crestone will use to communicate with your SAP system.
The RFC destination provides the secure transport channel for Crestone to execute remote-enabled function modules.
Prerequisites
- SAP GUI (SAP Logon) access to the target system/client.
- Technical user dedicated to Crestone integration with the role
ZCRESTONEassigned (see Step 4). - Hostname/IP, system number (SYSNR), client, and logon language for the SAP application server where Crestone will connect.
1) Open the RFC configuration
- Log in to SAP with a user authorized to maintain RFC destinations.
- Launch transaction
SM59(RFC Destinations). - In the navigation tree, expand TCP/IP Connections.
- Click Create (or use Display/Change → Create).

2) Maintain the RFC destination
Fill the tabs as follows:
Technical Settings
- RFC Destination:
CRESTONE_SERVER. - Connection Type: Select
T(TCP/IP Connection). - Description: Provide a short purpose (e.g., "Crestone integration").
- Activation Type: Choose
Registered Server Program. - Program ID: Set a unique identifier (e.g.,
CRESTONE_SERVER). This must match the ID configured in the Crestone connector. - Leave Gateway Host and Gateway Service with the default values for your SAP system unless BASIS specifies otherwise.
No logon credentials are required for TCP/IP destinations. Save the destination when the fields are complete.
Click Save when the fields are complete.

3) Test the connection
- With the new destination selected, choose Connection Test.
- Confirm you receive status Connection test OK.
- If any errors appear, verify that the Crestone connector is running and registered with the same Program ID, and confirm network/firewall settings permit the registration.

4) Configure SAP Gateway security
- Access transaction
SMGW. - Navigate to Goto ▸ Expert Functions ▸ External Security ▸ Maintain ACL Files.

- In the secinfo file, add the standard entry that allows program
CRESTONE_SERVERto start, specifying:TP:CRESTONE_SERVERHOST: the application server host name or*(per security policy)USER: the SAP user permitted to start the program (often*for registered programs)

- In the reginfo file, add the standard entry that allows program
CRESTONE_SERVERto register from the connector host, for example:TP:CRESTONE_SERVERHOST: connector host/IPACC:*(permitted users/clients)

Coordinate these ACL entries with your BASIS/security team; incorrect values can block gateway registrations or expose the gateway unnecessarily.
Verification
- The RFC destination appears under TCP/IP Connections with a green status icon.
- Connection tests complete without errors.
- Logs in transaction
SM59show successful registration/test timestamps.
Summary
- Create a TCP/IP RFC destination in
SM59with connection typeT. - Set the destination name and Program ID to
CRESTONE_SERVER(or your agreed identifier). - Save and test the destination to confirm successful registration and connectivity.
- Configure SAP Gateway security