converting RAC archive log mode to non archive log mode.

( Note All these steps are just indicative , run these on your test environment , before production )

- shutdown all instance except one

- restart your one instance in mount state which you have left in read - write mode on which you are going to
  perform this

- alter system set cluster_database=false scope=spfile sid='*';

- shutdown immediate

- startup mount;
 
- alter database noarchivelog;

- alter system set log_archive_dest='' scope=spfile sid='*';
 
- alter system set cluster_database=true scope=spfile sid='*' ;

- Startup all instances