tnsping

In the past and also recently I hit the specific case where TNSPING, AFAIK the TNS debugging tool, to provide incorrect feedback.

You see, what I expect is this : if I TNSPING to a connect string, and TNSPING replies with success, I assume that SQLPLUS can connect using the same TNS string. Obviously, there is a user and a password involved then as well, but we assure this to be correct.

But, TNSPING says OK, and then SQLPLUS fails to connect. I must check the actual error message but some way it doesn't matter as in this specific case, it's TNSPING which provides an incorrect response. It's not a bug if a success/failure testing tool provides the wrong result, that's major functionality broken.