Re: SQL*Net Connection Problem ERROR: ORA-12545

Sounds like a problem with tnsnames.ora. This file is used by sql*net to locate the instance. It lets you enter a "connetion name", like a logical instance name, and resolves the host ip address, port and oracle sid values to talk to the listener. The people that can connect probably have a file called tnsnames.ora under the $ORACLE_HOME/network/admin, typically C:\OraNT\network\admin or C:\OraWin95\network\admin directory. Find this file and copy it to the client locations.

While you are at it, get sqlnet.ora from the same place. Check sqlnet.expire_time and set it to a reasonable value, like 30. This will enable dead-sesion detection so that when people disconnect ungracefully (common occurance with a RAS dialup, right?) then the instance will eventually figure it out and kill their Oracle session after rolling back any uncommitted transactions and releasing locks. Kind of important. The value of the parameter is the number of minutes between "probes" from the server to the client. Note that this will not disconnect an idle client since the client sql*net process will respond to the probe if it can. It will only fail if the probe packet can't get there or if the client got shut down, as with a power failure.

Roger Snowden
Senior Systems Engineering Specialist
Oracle Corporation
NOTrsnowden_at_NOTus.oracle.com <-- to reply, remove the obvious

Srinivas wrote:
>
> Hi,
> We are trying to solve the
> following problem. I need help from u guys.
>
> Scenario:
> We have Oracle 7.3 running on Windows
> NT Server. NT is connected to the local
> network. Problem is all users who have
> access to the LAN and are able access
> WindowsNT machine
> are able to access Oracle without any problem.
>
> Some users login into LAN using modems (thru RAS connection).
> These users able to access Windows NT machine where
> Oracle 7.3 is running.
> These users could not connect to Oracle thru
> SQL*Plus. The error I got when tried was:
> ERROR: ORA-12545 TNS: Name lookup Failure.
> What is going on. And what
> should I do to resolve this problem.
> I appreciate any help in this
> problem solution. Thanks in advance.
>
> sincerely
> Srinivas
Received on Sun Dec 06 1998 - 00:00:00 CET