Re: Oracle EM and PL/SQL developer unable to connect to DB

From: Ora_DBA <>
Date: Sat, 31 Jan 2009 07:54:38 -0800 (PST)
Message-ID: <>

On Jan 31, 10:34 am, Ora_DBA <> wrote:
> I installed Oracle 10gR2 on Linux machine (CentOS Release 5). This
> machine uses DHCP protocol.
> I can't use EM from my PC to connect to the database.
> I made sure that the Entrprise Manager is up and running on the Linux
> machine.
> emctl status dbconsole
> TZ set to US/Eastern
> Oracle Enterprise Manager 10g Database Control Release
> Copyright (c) 1996, 2005 Oracle Corporation.  All rights reserved.
> Oracle Enterprise Manager 10g is running.
> Dropped and recreated EM repository using emca deconfig/config
> commands.
> Unlocked the syman account.
> Edited the entries in for the encrypted password.
> Stopped and restarted EM using emctl start/stop dbconsole command.
> But still the EM can't connect to the DB.
> I understand that this problem could be DHCP related. If so, is there
> a work-around?
> Also, I can not connect to the DB on the Linux machine using PL/SQL
> developer on my PC. I get ORA-12560 TNS Protocol adapter error.
> I made sure that the entry in my tnsnames.ora file on the PC is same
> as the one in the tnsnames.ora file on the Linux machine. On Linux
> machine, I can connect to the DB using SQLPlus.
> I stopped and restarted the listener on the linix machine.
> What else should I check?
> Thanks in advance.

I also made sure that the ports on the linux machine ( 1158 and 1521 ) are open.

When I use TNSPing command from my PC, it returns an error.

C:\Documents and Settings\sdharmadhik2>tnsping asndb

TNS Ping Utility for 32-bit Windows: Version - Production on 31-JAN-
009 10:52:18

Copyright (c) 1997, 2005, Oracle. All rights reserved.

Used parameter files:

Used TNSNAMES adapter to resolve the alias Attempting to contact (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = EBEST-1. = 1521)) (CONNECT_DATA = (SERVER = DEDICATED) (SERVICE_NA
E = asndb)))
TNS-12560: TNS:protocol adapter error Received on Sat Jan 31 2009 - 09:54:38 CST

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