ORA-12154 Connecting with Microsoft ODBC driver

[dmroubles]

hi, guys,

need help desperately. I have an Oracle 8i v. 8.1.5.0.0 on Windows NT. I have a front-end application written in C accessing it through Microsoft ODBC for Oracle. I always get the error "ORA-12154 TNS could not resolve service name" whenever I connect to the database using the Microsoft ODBC driver. I have already setup my Tnsnames.ora using Net8 Assistant and is as follows:

EPPIC =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = cnow)(PORT = 1521))
)
(CONNECT_DATA =
(SERVICE_NAME = EPPIC)
)
)

I've tried using Tnsping and I get the error "TNS-03505: Failed to resolve name".

Using the same service name, "EPPIC", I am able to connect to the database using Oracle ODBC Driver. I am really at a loss here.

The Microsoft ODBC driver for Oracle I am using is v. 2.273.6526.00, while the Oracle ODBC driver version is 8.01.05.00.

Thanks for replying to this query.
.

[marist89]

Before you get ODBC working, make sure you can connect to the box using sqlplus. If you can get sqlplus working, you can get ODBC working.

The steps I use to resolve networking issues are:
1. try to ping the server from the client. If it fails, you have a TCP/IP networking issue.
2. try to tnsping the database from the server. If this fails, you probably have a problem with your listener.
3. Try connect to the database using a loopback test from the server. If this fails, you probably have a tnsnames.ora problem.
4. try to tnsping the database from the client. If this fails, you problably have a naming issue on the CLIENT (tnsnames.ora).
5. try to connect to the database using sqlplus from the client. If this fails, you probably have a naming issue on the client.

[elaine3839]

Jeff,

Can you elaborate what is the 'loopback test' you mentioned in step 3?

Thanks!

[marist89]

Oh, sorry, I meant to elaborate on my original post.

A loopback test is when you try to connect to the server from the server using a sqlnet alias. For example, say your ORACLE_SID=test and your TNSNAMES.ORA alias is TEST.WORLD.

If you can connect via IPC:

dev% export ORACLE_SID=test
dev% sqlplus system/manager

then at least your database is up. Then, you can perform a loopback test using the tnsnames.ora alias:

dev% export ORACLE_SID=prod
dev% sqlplus system/manager@test.world

This way, you are verifying that you have the listener working correctly and that you have a valid tnsnames.ora alias on the server. The next step is to just copy the correct tnsnames.ora alias to the client and Voila!, you're done.

[molonede]

Why not just use the Oracle ODBC driver you already have working?