Client Connection database error, ORA-12516: TNS: Listeners cannot find available handle matching protocol stack

Problem description: Client Connection database error, ORA-12516: TNS: ListenerProgramUnable to find the available handle matching the protocol stack

 

Solution Process:
1. Check the current session count, processes, and sessions values, and find that the number of sessions and the values of the two parameters are very close.
SQL * Plus: Release 10.2.0.1.0-production on Monday October 9 15:50:21 2006 copyright (c) 1982,200 5, Oracle. All rights reserved.

SQL> Conn/As sysdba
Connected. SQL> select count (*) from V $ session;
Count (*)----------
45

SQL> show parameter Processes
Name type value ------------------------------------ ----------- ---------------------- aq_tm_processes integer 0
Db_writer_processes integer 1
Gcs_server_processes integer 0
Job_queue_processes integer 10
Log_archive_max_processes integer 2
Processes integer 50

SQL> show parameter sessions
Name type value ------------------------------------ ----------- ---------------------- java_max_sessionspace_size integer 0
Java_soft_sessionspace_limit integer 0l
Icense_max_sessions integer 0
License_sessions_warning integer 0
Logmnr_max_persistent_sessions integer 1
Sessions integer 60
Shared_server_sessions integer

2. Modify the values of processes and sessions
SQL> alter system set processes = 300 scope = spfile;
The system has been changed.
SQL> alter system set sessions = 300 scope = spfile;
The system has been changed.
 

3. View the processes and sessions parameters, but the changes do not take effect.
SQL> show parameter Processes
Name type value ------------------------------------ ----------- ---------------------- aq_tm_processes integer 0
Db_writer_processes integer 1
Gcs_server_processes integer 0
Job_queue_processes integer 10
Log_archive_max_processes integer 2
Processes integer 50
SQL> show parameter sessions
Name type value ------------------------------------ ----------- ---------------------- java_max_sessionspace_size integer 0
Java_soft_sessionspace_limit integer 0
License_max_sessions integer 0
License_sessions_warning integer 0
Logmnr_max_persistent_sessions integer 1
Sessions integer 60
Shared_server_sessions integer

4. Restart the database for the change to take effect
SQL> shutdown immediate
SQL> startup
SQL> show parameter Processes
Name type value ------------------------------------ ----------- ---------------------- aq_tm_processes integer 0
Db_writer_processes integer 1
Gcs_server_processes integer 0
Job_queue_processes integer 10
Log_archive_max_processes integer 2
Processes integer 300
SQL> show parameter sessions
Name type value ------------------------------------ ----------- ---------------------- java_max_sessionspace_size integer 0
Java_soft_sessionspace_limit integer 0
License_max_sessions integer 0
License_sessions_warning integer 0
Logmnr_max_persistent_sessions integer 1
Sessions integer 335
Shared_server_sessions integer

The last test to increase the number of connections to 50,100 are not reported ORA-12516 error.

 

This article from the csdn blog, reproduced please indicate the source: http://blog.csdn.net/jerry_of/archive/2007/06/05/1639217.aspx