ORA-00059 Maximum Number Of DB_FILES Exceeded

Dear colleague,

I got error message as subject while adding datafile.

my environment is IBM AIX with RAC 2 nodes 10.2.0.4. spfile stored on diskgroup, shared to both node 1 and node 2.

1) my question is, can I do rolling bounce while changing db_files parameter as command below,  ?

alter system set db_files=x scope=spfile;

2) can I apply below command to my db, do I need to restart both instances ?

alter system set db_files=x scope=spfile sid="*";

Regards,

Andes