ORA-12560:TNS: Protocol Adapter Error ORA-12154:TNS: The specified connection identifier could not be resolved

During the national day, when the database stored procedure calls the stored procedure through the Dblink cross-Library, the Ora-12560:tns: Exception Log for the protocol adapter error is logged in the error log.

Occasionally when connecting to a database with PL/SQL, you are frequently prompted:Ora-12154:tns: Unable to resolve the specified connection identifier

Then, Baidu a lot, tried a lot of methods, no answer to indicate is because the number of connections exploded (this is the root cause later found)

How to log the number of connections in the query:

Connect the database to the machine, enter CMD, and then type: Netstat-ann | Find "TCP"/C (Statistics, total connections)

Finally restarted the database of the machine, just fine (restart the Oracleservice service, Tnslistner service, etc. still cannot be released, it should be I did not find the appropriate method, finally forced to take a reboot)

ORA-12560:TNS: Protocol Adapter Error ORA-12154:TNS: The specified connection identifier could not be resolved