Question

I have a C# Windows IIS server (Windows Server 2003) application connecting to an Oracle database hosted on Linux (10gR2 on Red Hat 5.3). Intermittetly, Oracle throws an ORA-3113: end-of-file on communication channel error. This screws up the OracleConnection object in C#. Then, any new OracleCommands that try to use the OracleConnection all fail saying the connection has been closed.

I have reviewed the Oracle trace files generated by this error and have isolated the problem to faulty network hardware and am working to fix it.

However, I need to make my C# code more robust and have it respond appropriately to this error by closing and not using that connection object anymore. It is easy to catch the exception in C#, but I cannot reproduce the network issue in the Development environment to prove my code works & cleans up after itself.

try
{
  oracleCommand.ExecuteNonQuery();
}
catch(OracleException exception)
{
  if(exception.Code == 3113)
    CloseAndCleanup();
}

I have tried coding a PL/SQL trigger on a table that throws an ORA-3113 when I try to INSERT into the table.

CREATE OR REPLACE TRIGGER SCHEMA.TABLE
BEFORE DELETE OR INSERT OR UPDATE
ON SCHEMA.TABLE
FOR EACH ROW
DECLARE
  CONNECTION_LOST_CONTACT   EXCEPTION;
  PRAGMA EXCEPTION_INIT (CONNECTION_LOST_CONTACT, -3113);
BEGIN
  RAISE CONNECTION_LOST_CONTACT;
END;

This throws the right error, but doesn’t corrupt the OracleConnection object in C#. I can still send commands to the OracleConnection and it works.

How can I accurately simulate the ORA-3113 error?

Answer 1

ORA-3113 means that a server process/thread that was assigned to a client unexpectedly died or was killed deliberately.
You can produce ORA-3113 error by manually killing a server process/thread. Killing session wont produce that error.

To reproduce that error you can take following steps:

1) Determine server process/thread associated with your session

select p.spid  -- process ID
     , s.program  -- your oracle client
  from v$process p
  join v$session s
    on p.addr = s.paddr 

On the server side

2) Use orakill (windows) or kill -9 .. (Linux) to kill server thread/process

Windows example

c:\> orakill ORACLE_SID spid

After that you will get the ORA-3113 on the client side.