Connect to Remote Database - ORA-12154

Question

When attempting to use OCI to attach to a remote database I cannot resolve the service name.
However, I am able to connect using tnsping.
Example output is:
bash-2.03$ bin/msgoptim mo password mo
Message Optimiser - Version 1.0
Oracle DB Initialising
Database Access Error - ORA-12154: TNS:could not resolve service name
Abort (core dumped)
bash-2.03$ tnsping mo
TNS Ping Utility for Solaris: Version 8.1.7.0.0 - Production on 03-APR-2003 11:28:14
(c) Copyright 1997 Oracle Corporation. All rights reserved.
Attempting to contact (ADDRESS=(PROTOCOL=TCP)(HOST=qld)(PORT=1521))
OK (0 msec)
The remote database name is fed to the OCIServerAttach call as in :
checkerr( errhp, OCIServerAttach( svrhp, errhp, (text*) server.c_str(),
(sb4) server.length(), 0));
Am I doing this in the correct location, or am I missing something else in the process for remote databases.
I have no trouble connecting to a local database with a empty string in the OCIServerAttach call.
Thanks in anticipation.

Answer 1

ORA-12154: "Could not resolve service name"
ORA-12541: "No listener"
ORA-12154: "Could not resolve service name"
When you try to connect to your database through Developer, try using the connect_string you've been using with .world added to it (sometimes it's appended to your connect_string automatically, and if your sqlnet.ora file has NAMES.DEFAULT_DOMAIN and NAME.DEFAULT_ZONE set to anything other than 'world' then you may have to create a new sqlnet.ora file and set NAMES.DEFAULT_DOMAIN and NAME.DEFAULT_ZONE to world for it to work properly.
ORA-12541: "No listener"
You just need to verify that the listener is running and also is listening for the SID or CONNECT_DATA value being sent be PL/SQL Developer. For example, if the listener on your remote machine is listening for 'pl_sql' but when you try to connect to the remote database the PL/SQL Developer is sending a request to connect to 'plsql', then there is 'no listener' listening for 'plsql' and it fails. IF you can connect to the remote database via sqlplus, but then when you try it from PL/SQL Developer and it fails, that means the listener is in fact running, but not listening for the correct string being sent to it by the application.
Hope this helps.
Roy