urgent -- strange Net8 errors

I'm having intermittent TNS problems. The more I troubleshoot, the weirder it gets. I'm absolutely stymied; any help at all would be appreciated. Here are the symptoms:

-When I try to connect username/passwd_at_db01, -soemtimes- it connects and
-sometimes- I get an error. When I'm on the server on a console window,
the error I get is always ORA-03113. ("end-of-file on communication channel") But it's not consistent; sometimes I can connect fine.

-When I try to connect to the databases from another machine, I get
various errors: 12545, 01034 (Oracle not available), 12541 (Listener not available -- even if the listener is running). In the past, the connecitons were working fine. I then added a couple more databases to the same machine, (there are now five), and slowly the ability to connect became more erratic until I cannot get trhough at all. ?

-For no apparent reason, sqlnet.log is not logging these errors, even
though i set trace_level = admin in sqlnet.ora. When I look at sqlnet.log (on the server), all I see is "Fatal NI connect error 12153" -- which, since I'm trying to connect to the server from the server, and the server is indeed on the network, doesn't make any sense to me -- and "Tracing not turned on" -- how the heck do I turn tracing on, if not in sqlnet.ora?

-Here is something really weird. When I trcroute the server from another
machine, *it takes the listener down*. I dont' even understand how this is possible. Do you have any idea what might be going on? When I tnsping, the connections to the databases go though fine, but when i trcroute, it takes the listener down.

Thanks very much,
Natalka Roshak

--

He stands proud in his uniform
He knows he's made it now
He's been told he'll be a hero
But he hasn't been told how
He receives his plastic key to heaven
Takes his holy vow
Then he turns,
Then he's gone

                                --Peter Ulrich, "Taqaharu's Leaving" Received on Fri Feb 11 2000 - 04:27:59 CST