Re: ora-03113 end-of-file on communication channel

Семенова Ольга wrote:

> The impression such, that Oracle simply has not time to transfer the
> information SQLPLUS
> For any reasons; and at subsequent startup too we receive a mistake
> ( ora-27101 shared memory realm does not exist).
> What to make? The server (cluster with Oracle 9i).

"end-of-file on communication channel" means exactly what is says.

end-of-file = channel closed/terminated/torn up/shutdown

communcation channel = TCP socket connection between the server and the client

If a database instance goes down, then all its server processes goes down. Some of these server processes will be dealing with client sessions.

Such a server process (also called a shadow process) will perform a rollback on any open transactions, close all open cursors, release memory and do all kinds of cleanup. It will also cause the the socket handle to the client to be closed.

The client detects the socket handle being closed and raises the ORA-03113 error. It has no longer an open communication channel to the database.

An immediate shutdown is of course not the only time that an ORA-03113 can occur.

If you for example (in Unix) kills the shadow process, you will also cause the immediate close of that socket handle of that shadow process. Which means that the client on the otherside of that socket connection will get an ORA-03113.

--
Billy