Reconnect R/3 source system after BW systemcopy ?

Question

We want to copy our BW 3.0b development system as a BW sandbox system in order to try out the BW 3.5 migration.
Therefore, we performed a system copy of our BW DEV system to a new machine. On the BW-side we ran BDLS to get a new logical name for the system and defined a RFC connection to our R/3 Dev Source System (incl. appropriate RFC users).
On the R/3 side we also defined an additional RFC connection to the "new - just copied" BW-system.
While trying to reconnect our R/3 Devopment source system within the new BW we encountered the problem that the R/3 system recognized that there already exists a connection to a BW (the old BW dev). If we take this option, the old connection is deleted and a new one is defined. However, from the R/3 perspective we want two BWs connected. It seems the problem has to do with the IDOCs and TRFC port definitions, because the IDOC type ZRSBW010 seems to point to the wrong system.
Unfortunately, we are stuck at the moment.
Any kind of help or hints to relevant SAP documents would be much appreciated.
In the OSS we found some notes on this topic (325525 etc.) but we still not sure how to proceed.
However, in general, we think it shouldn't be a problem to have one R/3 connected to several BW's or is it?
Frank Schülke, E.ON Ruhrgas IT, Germany

Answer 1

Frank,
It is possible to connect a copy of your BW dev. system to the same R/3 system. The problem you are experiencing is related to the connection ID from table RSABASIDOC. This is a unique ID in your system (normally the first two characters of your source system name). Tis ID is in RSBASIDOC in yuor BW and R/3 system. When you copy your BW and try to connect it to your R/3 system again, you will get the conflict you already noticed.
The solution is to run SE37 --> RSAP_BIW_DISCONNECT in your new BW system (make a screen shot first of the RSBASIDOC entry!). This will be cleared by the function module. You will notice that the source system is not visible anymore is RSA1. However all the transfer rules etc. are still there (invisible). This would not be the case when you are doing a remove source system in RSA1 as suggested.  Now you can create the source system again via the normal way. Use exactly the same name for the source system mas you made it via the BDLS. During this process the BW and R/3 systems are "negociating" a new unique connection ID for this BW-R/3 connection. This creation of the source system will also make all the related info visible again (like transfer rules).
Note in general: If you get a screen saying the connection ID is already used, ALWAYS choose DO NOT DELETE. After chosing DELETE there is no way of solving the issue other then restoring the system from backup! In this case you would delete everything in your R/3 system regarding the original BW system! When you get the message, check RSBASIDOC in both systems as there will be a conflict.
Regards,
Sander.