ora-00600, ora-44303 and ora-44775 after cloning a remote pdb

These days we had an incident with a 19.6 Oracle database on MS Windows. We have cloned a PDB like we have done it a lot times before using a database link. I already have written some blog posts about that (and you can download the scripts there). 

The "create pluggable database XXXY from XXXX@clone_source refresh mode manual;" succeded, but when we tried to open the pdb, it failed with

ERROR at line 1:
ORA-44303: service name exists
ORA-44775: Pluggable database service cannot be created

The crazy thing is, this is the first time we tried to clone the database to this fresh and empty CDB. 

The alert.log had an additional entry:

ORA-00600: internal error code, arguments: [kpdbIdToTenantKey1], [4099], [], [], [], [], [], [], [], [], [], []

While querying sys.cdb_service$ we have analyzed that the service name was in lowercase letters, while all other service names can be found there in uppercase. 

With this information we have found a bug at MOS - there are different operating system where you can find a patch for - unfortunately not for MS Windows:

Patch 31143870: CORE DUMP DURING DBMS_SERVICE.START_SERVICE USING CASE SENSITIVE NAME FOR PDB

It seems that this is fixed not so long ago as it can be downloaded as one-time fix for 19.10.0.0.0 DBRU (which was released 2 weeks ago).

If you run into this, please try first to install the patch - we weren't able to test it, but it seems it could fix this problem also. 

If this does not fix this problem or if you are on a platform (like MS Windows) where the patch isn't available yet, you may try the workaround that helped us:

delete the wrong (lowercase) service name from sys.cdb_service$ (and if it exists also from sys.service$). Don't forget to commit. 

Afterwards unplug, drop and plugin the PDB again - for us this was working well. The PDB was cloned successfully and we were able to open it without any error. 

Comment: Feb., 22nd, 2021. The 19.10 Bundle is now available also for MS Windows.