Program

BIOVIA Direct (all versions)

Operating System

Microsoft Windows Server (as supported by the installed BIOVIA Direct version)

Summary

As previously reported this post again points out a problem with the Oracle 19c Database Bundle Patches 19.24, 19.25, and 19.26 which leads to malfunction of all BIOVIA Direct versions in use. The problem manifests itself in the fact that an Oracle error "ORA-28576: lost RPC connection to external procedure agent" regularly occurs when calling Direct functions, and the call therefore fails. The source of the problem is an Oracle bug that was first introduced with the quarterly Oracle bundle patch 19.24.

Error Details

The problem is intermittent and affects a large part of the BIOVIA Direct functionality. If you are affected by this problem, BIOVIA Direct may still work in some cases, but typically you will run into problems very quickly while you use Direct continuously.

The full error message typically looks like this:

ORA-28576: lost RPC connection to external procedure agent
ORA-06512: at "C\$DIRECT2025.MDLAUXOP", line 2270
ORA-06512: at "C\$DIRECT2025.MDLAUXOP", line 2267
28576. 00000 -  "lost RPC connection to external procedure agent"
*Cause:   A fatal error occurred in either an RPC network connection,
          the extproc agent, or the invoked 3GL after communication had
          been established successfully.
*Action:  First check the 3GL code you are invoking; the most likely
          cause of this error is abnormal termination of the
          invoked "C" routine. If this is not the case, check for
          network problems. Correct the problem if you find it. If all
          components appear to be normal but the problem persists, the
          problem could be an internal logic error in the RPC transfer
          code.  Contact your customer support representative.

The problem is not specific to BIOVIA Direct but potentially affects all applications that use Oracle's Heterogeneous Services. With regard to BIOVIA Direct, BIOVIA has so far only been able to observe this problem reproducibly on the Windows platform. On this platform, the problem also generates the following specific entry in the trace files of the Oracle Heterogeneous Service in %ORACLE_HOME%\hs\trace:

HS: RPC error reported on agent, ExecCalloutCallbackIn: ..._TransferAgtDEs; NCR code 1009

Solution

As far as we know at the time of this post, the Oracle bug occurs with the quarterly Oracle Release Updates or Database Bundle Patches 19.24, 19.25, and 19.26. Oracle lists this bug with the title 'ORA-28576: LOST RPC CONNECTION TO EXTERNAL PROCEDURE AGENT' under the bug number 36551493. The bug report currently contains no further details.

Oracle also provides patches under this bug number 36551493. BIOVIA recommends its customers to apply this patch to restore the BIOVIA Direct functionality. If required, please contact Oracle Support for further details on this bug.

Please note that Oracle has released different patches under the same patch number for each of the bundle patches 19.24, 19.25 and 19.26. Therefore, please make sure that you install the individual patch that matches your bundle patch. Please also note that you cannot update a bundle patch with the additionally installed patch 36551493 directly to the next higher bundle patch. Instead, you must first remove the patch 36551493, then install the next higher bundle patch, and then install the patch 36551493 for the next higher bundle patch.

[Update] It seems like Oracle has finally added the required patch 36551493 to their quarterly Oracle Bundle Patch 19.27 for Windows (Oracle patch 37532350).