If we are changing spfile in oracle RAC, then we need to use additional SID parameter in the alter system command.
Here SID is the instance_name.
For changing the parameter in both the instances of the RAC.
alter system set SEC_CASE_SENSITIVE_LOGON=FALSE scope=both sid='*';
For changing the parameter in a specific instance.
alter system set job_queue_processes=500 scope=both sid='ORCL1';
If we don-t mention the SID parameter, then by default it will be configured for the local instance, from where we are executing the command.
There are 3 options for SCOPE parameter:
1. MEMORY - the change is immediate but will not be available post instance restart
2. SPFILE - the changes will be made to spfile, however it will be applied the database, post instance restart
3. BOTH - Changes will be applied to database immediate, And it dont needs database restart
RAC HOW TOORACLE RAC