Oracle Database 19c: RAC, ASM, and Grid Infrastructure Administration Free Sample Questions

The error message CRS-2527 explicitly states the server pool is not active on the target server. In a policy-managed cluster, resources are tied to server pools. If a server is not part of a pool's server list, the pool cannot be active there, and consequently, its member resources cannot start. The most direct resolution is to add the target node to the server pool's list of candidate servers using srvctl modify serverpool.

Hash partitioning distributes DML across different partitions and their underlying index segments, effectively spreading out the 'hot spots' and reducing contention on a single index leaf block.

Using a large sequence cache with NOORDER allows each instance to have its own range of sequence values. This prevents all instances from competing for and inserting into the same right-hand index leaf block, which is a classic cause of 'gc current block busy' waits.

Cache Fusion is the core technology of RAC that enables instances to share data without writing it to disk first. It uses the high-speed private interconnect to ship data blocks from one instance's buffer cache to another's, satisfying read or write requests much faster than a disk I/O operation would. This process is managed by the Global Cache Service (GCS).

This is a fundamental architectural requirement for Oracle RAC. Each instance manages its own transactions and requires its own UNDO tablespace. Because any instance may need to perform recovery on a transaction initiated by another (failed) instance, all UNDO tablespaces must be on shared storage accessible to all nodes in the cluster.

The key requirement is the recovery of in-flight transactions without user interruption. This is the precise function of Application Continuity (AC). AC records the session and transactional state, allowing it to be replayed on a surviving instance after a failure, making the outage transparent to the application. TAF is an older technology that primarily replays SELECT statements and does not recover the full transactional state.

This allows the administrator to control exactly when the I/O-intensive rebalance operation occurs, minimizing impact on the workload by running it during off-peak hours.

Proper failure group design is crucial for ASM's striping and mirroring. Adding disks to a new failure group (or distributing them among existing ones) is necessary for ASM to maintain redundancy and balance data correctly.

The goal is a balance between speed and workload impact. POWER 1 is too slow. A very high power would impact the workload too much. A moderate power like 4 is a common choice to make good progress without causing severe performance degradation.

The Cluster Synchronization Services Daemon (CSSD) is responsible for cluster integrity and node membership, which requires access to voting disks. The log message "Waiting for voting disk access" is the key indicator. Since CSSD on node1 is online, it has successfully accessed the voting disks. The failure of CSSD on node2 to come online, combined with the log message, strongly points to a loss of connectivity from node2 to the shared storage where the voting disks reside.

This is a primary use case for Flex Clusters. Leaf Nodes can host database instances but do not require direct access to storage. They connect to ASM instances running on Hub Nodes over the ASM network. This reduces storage network traffic and is ideal for scalable, read-intensive workloads where direct, high-bandwidth storage access from every node is not critical.

The correct way to control PDB placement and workload in RAC is through services and server pools. By creating a server pool with only the desired nodes and then creating a service for the PDB that is assigned to that pool, you ensure that connections to that PDB (via the service) are routed only to the specified nodes, and the PDB will only be active on nodes within its assigned pool.

The zero-downtime patching process involves multiple phases. First, opatchauto apply -prepare-clone is used to prepare the new home. After this is done on all nodes, opatchauto apply -deploy-clone is run. This command performs the switchover by stopping the old GI stack and starting the new, patched GI stack in a rolling fashion across the cluster, ensuring the cluster remains operational throughout the process.