Create Dblink encountered Ora-12154:tns: Unable to resolve the specified connection identifier problem

Create Dblink:

Toad creates a library-to-B graphical interface through a graphical interface:

The first step:

Step Two:

The last step is an error:

First, through the detection of A and B libraries of the server can ping each other to ensure normal communication;

Then, by examining the Tnsnames.ora file, we found that TNS was configured in the Tnsnames.ora file with both A and B libraries, and there was no problem;

It's annoying to test the dblink of a library to C library by repeatedly creating tests or not being able to create them successfully.

Test in B library created to a library dblink, can be created and normal use;

Did not, degree Niang, found that Tnsnames.ora exist Oracle server, and Oracle client, if only the client is configured, and no configuration server will be reported TNS error, so try to a library B library in the service side, respectively configuration B library and a library TNS;

Results, through repeated testing or not be able to create success, immediately furious;

Finally rage, whether or not to configure TNS, will configure the B-Library TNS describe, directly configured to the graphical interface created by the database such as:

After this, the direct creation of success, test success, completely no problem, but the root cause of the problem has not been identified, pending further exploration ...

Create Dblink encountered Ora-12154:tns: Unable to resolve the specified connection identifier problem