Re: ORA-3113 errors, suddenly

Terry G. Phelps wrote:
>
> After a year of relatively trouble-free Oracle running, first on 7.1.3
> and lately on 7.1.6, I started getting ORA-3113 errors today. I don't know
> if it's relevant, but I recently upgraded my RS/6000 AIX from 3.2.5 to
> 4.1.4, and then, just a few days ago, moved all applications and data to a
> new physical server, still running 4.1.4.
>
> I'm getting the errors on both server "batch" processes, and also on client
> PC applications running SQLNET 1. What exactly does this 3113 error mean??
> The error text says "end of file on communications channel" or something.
> Is the Oracle connection being lost? What should I do to fix this, or at
> least to isolate the problem. This is becoming a serious issue quickly.

All oracle connections involve some sort of communication channel between a client process and a server process. The channel can be as simple as a unix pipe or as complex as an SQL*Net connection through multi-protocol exchanges.

The client process uses ORA-3113 if the channel closes unexpectedly. The usual cause is that the server process has terminated suddenly (i.e. crashed).

You have to find out why your server processes are crashing. Look for trace files in $ORACLE_HOME/rdbms/log, core files, syslog messages, the alert log, the oraserv log etc. etc.

These incidents can be hard to track down. Some time ago we had an incident in which we got 3113 errors on SQL*Net V1 connections. They were sporadic, and quite rare, and we could find no traces of the crashed processes on the server. It turned out that oraserv had accidentally been started with a 5 minute hard CPU limit. Oraserv itself would take several weeks to use that much CPU, but all SQL*Net server processes were inheriting the limit. Whenever anyone tried to do something expensive, their server process would crash.

Charles Jardine, University of Cambridge (UK) Computing Service Received on Fri Apr 19 1996 - 00:00:00 CEST