[grid@ydb1 ~]$ crsctl status res -t -init
  
ora.ctssd
      1        ONLINE  ONLINE       ydb1                  OBSERVER

[grid@ydb1 ~]$ crsctl check ctss
CRS-4700: The Cluster Time Synchronization Service is in Observer mode.
[grid@ydb1 ~]$ exit
logout
[root@ydb1 ~]# mv /etc/ntp.conf /etc/ntp.conf.bak

[grid@ydb1 ~]$ crsctl check ctss
CRS-4701: The Cluster Time Synchronization Service is in Active mode.
CRS-4702: Offset (in msec): 0
[grid@ydb1 ~]$
[grid@ydb1 ~]$ crsctl stat res -t -init
                                   
ora.ctssd
      1        ONLINE  ONLINE       ydb1                  ACTIVE:0            

RAC所有节点都要执行。