Oracle cluster ODP.net Distributed Transaction Coordinator data loss

Question

This is ASP.NET 4.0 application which is using Oracle cluster through ODP.net and Distributed Transaction Coordinator/MSDTC. In System.Transactions.TransactionScope transaction, it saves data in two different databases (db1 and db2). It commits transaction only if both save operations are succeeded.

It had been working fine until Monday. Now this happening intermittently that data is getting deleted from one database(db1 - save operation call succeeds) as soon as ASP.NET request is complete but another database(db2) has that data associated with this request. It happens intermittently, some time data is saved in both database while some time in one database only (db2). No exceptions are logged.

Only change on server is installation of ODP.NET 11.2.3.

Any idea what could be the reason?

Answer 1

We were having a problem with DTCs as well with 11.2.3. Not the same issue you are having, but a huge problem none-the-less. We were getting "ORA-24776: cannot start a new transaction" Oracle errors under heavy load. No errors were logged in the database and process tracing proved unhelpful. There was no code change other than the database update from 10g to 11g database. The 11.2.3 ODP drivers we were using worked perfectly against Oracle 10g. When we updated the database to 11g is when all the errors started. I searched and debugged for a month. The only thing that I have found that stopped this was updating to 11.2.4 which was released January 14. There is only X-copy deploys for this release and strangely there is not release notes for this particular update. We contacted Oracle to find what they have fixed with this release but they have failed to respond so far. I know this is an older posting I hope this helps!