Which three statements accurately describe the components of the Cluster Ready Services
Technology Stack?
A.
Cluster Ready Services (CRS): A specialized oraagent process that helps CRSD manage resources
owned by root, such as the network, and the Grid virtual IP address.
B.
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.
C.
Cluster Time Synchronization Service (CTSS): A background process that publishes events that
Oracle Clusterware creates.
D.
Event Management (EVM): Provides time management in a cluster for Oracle Clusterware.
E.
Grid Naming Service (GNS): Handles requests sent by external DNS servers, performing name
resolution for names defined by the cluster.
F.
Oracle Agent (oraagent): This process was known as RACG in Oracle Clusterware 11gR1 (11.1).
Explanation:
The following list describes the processes that comprise CRS: The CRSD manages cluster resources
based on the configuration information that is stored in OCR for each resource. This includes start,
stop, monitor, and failover operations. The CRSD process generates events when the status of a
resource changes. When you have Oracle RAC installed, the CRSD process monitors the Oracle
database instance, listener, and so on, and automatically restarts these components when a failure
occurs. 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.https://docs.oracle.com/database/121/CWADD/intro.htm#CWADD90956
B E F >
1. Upper Technology Stack
• Cluster Ready Services
(CRS/CSS/ASM/GNS/CTSS/EVM/ORAAGENT/ONS/ORAROOTAGENT)
• Daemon (CRSD)
2. Lower Technology Stack
• Oracle High Availability Services
(OHASD/ appagent/ ologgerd/GIPC/ GPNPD/ MDNS/ oraagent/ scriptagent /osysmond)
Cluster Ready Services (CRS) The primary program for managing high availability operations within a cluster. The crs process manages cluster resources based on the resource’s configuration information that is stored in the OCR. This includes start, stop, monitor and failover operations. Anything that the crs process manages is known as a cluster resource which could be a database, an instance, a service, a Listener, a virtual IP (VIP) address, an application process, and so on.
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 third-party clusterware, then the css process interfaces with your clusterware to manage node membership information.
Cluster Time Synchronization Service (CTSS): Provides time management in a cluster for Oracle Clusterware.
Oracle Notification Service (ONS): A publish and subscribe service for communicating Fast Application Notification (FAN) events
Event Management (EVM): A background process that publishes events that crs creates.
Process Monitor Daemon (OPROCD): This process is locked in memory to monitor the cluster and provide I/O fencing. OPROCD performs its check, stops running, and if the wake up is beyond the expected time, then OPROCD resets the processor and reboots the node. An OPROCD failure results in Oracle Clusterware restarting the node.
crsd: Performs high availability recovery and management operations such as maintaining the OCR and managing application resources. This process runs as the root user, or by a user in the admin group on Mac OS X-based systems. This process restarts automatically upon failure.
Oracle Agent (oraagent): Extends clusterware to support Oracle-specific requirements and complex resources. This process runs server callout scripts when FAN events occur. This process was known as RACG in Oracle Clusterware 11g release 1 (11.1).
Oracle Root Agent (orarootagent): A specialized oraagent process that helps crsd manage resources owned by root, such as the network, and the Grid virtual IP address.