ORA-00020: maximum number of processes (%s) exceeded



The issue is due to process/sessions parameter exceeds the limit. Need to increase those parameter to solve this issue.


When ORA-00020 occurred then you wont able to connect to the DB via sys user to change the parameter. You can use following steps to overcome the issue.

  1. Login to DB using following command
    [[email protected] 11.1.0]$ sqlplus -prelim “/ as sysdba”
  2. Shutdown the DB
    SQL>shutdown abort;
  3. Exit from session
  4. Connect to DB via sys
    [[email protected] 11.1.0]$ sqlplus / as sysdba
  5. Start the DB
  6. Check the Value for Process and sessions parameter
    SQL>select resource_name, current_utilization, max_utilization, limit_value from v$resource_limit where resource_name in (‘sessions’, ‘processes’);
  7. Change the Parameter values
    SQL> alter system set processes=300 scope=spfile;
    SQL> alter system set sessions=500 scope=spfile;