Which three statements are true about Oracle Clusterware components, architecture, and behavior?
A.
The Cluster Ready Services Daemon (CRSD) is responsible for monitoring and maintaining the availability of cluster resources defined in the Oracle Local
Repository file (OLR).
B.
All cluster nodes can write or read from the Oracle Clusterware Repository (OCR) file at the same time.
C.
The Oracle High Availability Services Daemon (OHASD) is responsible for monitoring and maintaining the availability of the Clusterware stack on a cluster node.
D.
Voting disks stored in Automatic Storage Management (ASM) can be discovered or used even if the ASM instance on a cluster node is down.
E.
The Cluster Synchronization Services Daemon (CSSD) must connect to the cluster by accessing the Oracle Clusterware Repository (OCR) file before the Oracle
High Availability Services Daemon (OHASD) is started.
F.
Time synchronization in an Oracle Cluster is possible without using network Time Protocol (NTP).
Explanation:
F: To activate CTSS in your cluster, you must stop and deconfigure the vendor time synchronization service on all nodes in the cluster. CTSS detects when this
happens and assumes time management for the cluster.
For example, to deconfigure NTP, you must remove or rename the ntp.conf file.
Incorrect Answers:
A: The CRS daemon (crsd) manages cluster resources based on the configuration information that is stored in OCR, not the OLR, for each resource.
B: You must update OCR through supported utilities such as Oracle Enterprise Manager, the Oracle Clusterware Control Utility (CRSCTL), the Server Control Utility
(SRVCTL), the OCR configuration utility (OCRCONFIG), or the Database Configuration Assistant (DBCA)
E: Please refer to the cluster startup picture below.
https://docs.oracle.com/cd/E11882_01/rac.112/e41959/intro.htm#CWADD90955
A wrong
The CRS daemon (crsd) manages cluster resources based on the configuration information stored in OCR for each resource. This includes start, stop, monitor, and failover operations.
B wrong
Each node in the cluster maintains an in-memory copy of OCR, along with the CRSD that accesses its OCR cache. Only one of the CRSD processes actually reads from and writes to the OCR file on shared storage
C CORRECT
The Oracle High Availability Services daemon (ohasd) is responsible for starting in proper order, monitoring, and restarting other local Oracle daemons, including the crsd daemon,which manages clusterwide resources.
D correct
Voting disks do not appear as regular files within ASM,
rather Clusterware records exactly where the voting disk information is located. This
arrangement exists so that if ASM is unavailable for any reason, Cluster synchronization Services can still access the voting disks and maintain the cluster.
E wrong
Cluster Synchronization Services (CSS): Manages the cluster configuration by controlling which nodes are members of the cluster and by notifying members when a node joins or leaves the cluster. If you are using certified third-party clusterware, CSS processes interface with your clusterware to manage node membership information. The cssdagent process monitors the cluster and provides I/O fencing. This service formerly was provided by Oracle Process Monitor Daemon (oprocd), also known as OraFenceService on Windows. A cssdagent failure may result in Oracle Clusterware restarting the node
F correct
if NTP not used you can use
Cluster Time Synchronization Service (CTSS): Provides time management in a cluster for Oracle Clusterware