The managed ABAP systems should be updated in the SLD. This can be done via rz70 transaction. The rz70 transaction automatically creates the SLD_UC and SLD_NUC RFC destinations.

You get during the test of the SLD_UC RFC connection in  sm59 "ERROR: Error (Msg DGW       748 not found".

This indicates, that the registartion of the TP program is not allowed on the gateway, where the SLD is registered.

1. Check, that you mainained a correct hostname for SLD gateway in rz70.

Go to the SLD ->Administartion->Details->Data Suppliers tab

Example:

In some cases you can see as well, that the RFC server threads are in [DOWN] state. In that case for the RFC server threads are not allowed to register on the gateway. This  may  happen, when the SLD gateway runs on a different host from the SLD host.

2. Go to the managed system, and check the rz70 settings. Here the hostname must be equal with the hostname of the gateway hostname (or IP name)

3. Go to the SLD gateway file.

Check the reginfo file:

go to transaction ==>smgw

                               ===> Goto

                                    ===>Expert Functions

                                       ===> External Security

Here can you find the reg_info file.

4.

The content of the reg_info  file must be corrected or enhanced with the host of the managed system hostname.

Here is important, if you add a new managed system's host name (or IP name) to reg_info, you should  add this new rule on the top of the reg_ino file. The reg_info file is evaluated top-down, and the most specific rules should be always on the topmost place.

5.

When you modify the reg_info file, you must reread this, in order it contains the new changes.

smgw->Goto->Expert function-> External security->reread

6. Sometimes it  is useful, that you deregister the existing registered SLD_UC and SLD_NUC TP progams.

SMGW > Goto > Logged on Clients > Delete Client

7. Test  again SLD_UC connection from managed system