ORA-03113: end-of-file on communication channel after long inactivity in ASP.Net app

ORA-03113: end-of-file on communication channel

Is the database letting you know that the network connection is no more. This could be because:

  1. A network issue - faulty connection, or firewall issue
  2. The server process on the database that is servicing you died unexpectedly.

For 1) (firewall) search tahiti.oracle.com for SQLNET.EXPIRE_TIME. This is a sqlnet.ora parameter that will regularly send a network packet at a configurable interval ie: setting this will make the firewall believe that the connection is live.

For 1) (network) speak to your network admin (connection could be unreliable)

For 2) Check the alert.log for errors. If the server process failed there will be an error message. Also a trace file will have been written to enable support to identify the issue. The error message will reference the trace file.

Support issues can be raised at metalink.oracle.com with a suitable Customer Service Identifier (CSI)


Add Validate Connection=true to your connection string.

Look at this blog to find more about.

DETAILS: After OracleConnection.Close() the real database connection does not terminate. The connection object is put back in connection pool. The use of connection pool is implicit by ODP.NET. If you create a new connection you get one of the pool. If this connection is "yet open" the OracleConnection.Open() method does not really creates a new connection. If the real connection is broken (for any reason) you get a failure on first select, update, insert or delete.

With Validate Connection the real connection is validated in Open() method.


Check that there isn't a firewall that is ending the connection after certain period of time (this was the cause of a similar problem we had)