The Qlik Replicate log reads:
00008260: 2021-12-08T10:31:08 [SOURCE_CAPTURE ]I: ORA-03113: end-of-file on communication channel Process ID: 14794 Session ID: 268 Serial number: 30476 [1022305] (oracle_endpoint_unload.c:1126)
Environment
ORA-03113: end-of-file on communication error means that the connection with the Oracle source database fails and we are unable to send or receive more events.
This can happen for several reasons:
- The server process servicing the client connection died unexpectedly, or the network communication between the Qlik Replicate server and the Oracle server was interrupted
- A firewall rule closed a connection due to a timeout (low activity between Oracle and Qlik Replicate).
- The Oracle database was not online when the error was logged
Resolution
Qlik Replicate works in a mode that is aware of the batches being processed by each component Source, Sorter and Target, meaning there is no need to worry about data being lost because of this error.
This is an environment issue that Qlik Replicate treats as a recoverable error. During CDC it will resume replicating the data from where it left off after the connection is reestablished. A Full Load cannot be resumed and has to start over.
How to troubleshoot and address the issue:
Check the Oracle Alert log at the time of the issue, see if any trace files were written, and then follow up with your DBA or Oracle Support for root cause analysis. A patch might be available from Oracle for the issue. Also see Oracle's documentation on this error: ORA-03113 - Database Error Messages (oracle.com)
A possible solution would be to add the following line to your SQLNET.ORA file:
SQLNET.INBOUND_CONNECT_TIMEOUT = 0
Along with adding the enable=broken parameter to the tnsnames.ora file, which will cause SQLNet to use keep-alive packets:
ORCL_REPLICATE =
(DESCRIPTION =
(ENABLE=BROKEN)
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP) (HOST = oracle_server.company.com)(PORT = 1521))
)
(CONNECT_DATA =
(SERVICE_NAME = orcl)
)
)
