Explanation:
NDB Multi-Cluster is a feature that allows multiple Nutanix clusters to share a common NDB service for database management and automation. NDB service consists of two components: NDB Server and NDB Agent. NDB Server is the central component that provides the web UI, REST API, and database orchestration logic. NDB Agent is the component that runs on each Nutanix cluster and communicates with the NDB Server to perform database operations.
When NDB Multi-Cluster is enabled on Cluster A, it becomes the primary cluster that hosts the NDB Server VM. Cluster B, which is registered with NDB, becomes a secondary cluster that hosts only the NDB Agent VM. Therefore, Cluster A has both NDB Server and NDB Agent, while Cluster B has only NDB Agent. This configuration allows Cluster B to leverage the NDB service running on Cluster A for database management and automation.

Explanation: The default continuous recovery for the Gold SLA in Era Time Machine is 30 days1. This means that the system keeps a continuous recovery point for the last 30 days, allowing you to restore your database to any point within this period1.

Explanation: For enabling Multi-Cluster management on an Era installation, the hypervisor version must be supported and port 9440 must be open between the Era VM and clusters. This ensures that the Era VM can communicate with the clusters for management tasks1.

Explanation:
In Nutanix Era, a Volume Group is the recommended storage provisioning method for a large I/O-intensive database that doesn’t support a multi-disk layout1. A Volume Group in Nutanix Era is a collection of disks that can be managed as a single entity, providing a way to aggregate the storage capacity of multiple disks into a larger storage unit1. This allows for better performance optimization as it enables the database to leverage the combined I/O capabilities of all the disks in the group1. It’s important to note that while other options like Load Balancing, Storage Spaces, and vDisk based provisioning can also be used in certain scenarios, a Volume Group is specifically designed for situations where a single, high-performance storage unit is required1.

Explanation:
Nutanix Era is a database management solution that automates and simplifies database administration tasks such as provisioning, patching, cloning, and backup. In the event of a database crash, the most effective way to minimize data loss and reduce restore time is to perform a restore of the source database by selecting the most recent point in time and including the Tail log Backup12.
The Tail log Backup includes all the transactions that have occurred since the last transaction log backup, which helps to minimize data loss. By selecting the most recent point in time for the restore, the administrator ensures that the database is restored to the state it was in just before the crash, thereby reducing the amount of data that needs to be reprocessed or reentered12. This approach aligns with the Nutanix Era’s capabilities and best practices for database recovery12.

Explanation: In the context of Nutanix Database Automation (NCP-DB), when there are insufficient resources on a development cluster, the administrator can adjust the Compute and Database Parameters profiles to make the copy fit within the available resources1. The Compute profile includes settings related to CPU and memory resources, which can be adjusted to fit within the available resources. The Database Parameters profile includes settings that control the behavior and resource usage of the database, which can also be adjusted to optimize resource usage1.

Explanation: Nutanix Era supports a variety of database engines, including Oracle, PostgreSQL, MySQL, and Microsoft SQL Server1. However, when it comes to rolling back a patch using the Command Line Interface (CLI), this feature is specifically supported for the Oracle database engine1. This allows for efficient validation of critical database updates and simplifies database rollback1. Please note that while Era does provide support for other database engines, the ability to rollback a patch using CLI is currently specific to Oracle1.

Explanation:
NDB supports PostgreSQL HA software profiles for provisioning PostgreSQL databases with high availability. PostgreSQL HA software profiles consist of three components: etcd, HAProxy, and Patroni.
etcd is a distributed key-value store that provides a reliable way to store configuration data across a cluster of machines. etcd is used by Patroni to store and synchronize the cluster state and configuration.
HAProxy is a load balancer that distributes incoming requests to the PostgreSQL nodes. HAProxy is used to expose a single endpoint for database connections even as the roles of the individual nodes change.
Patroni is a template for PostgreSQL high availability. Patroni is responsible for managing the state of the cluster and handling failover. Patroni uses etcd as the distributed configuration store and relies on HAProxy for load balancing.
Therefore, the software component that manages the state of the cluster and handles failover is Patroni.

Explanation:
According to the Nutanix Database Automation (NCP-DB) learning documents, to refresh an existing DB Clone, a developer with RBAC privileges in Era needs to navigate to Databases > Clones. From there, they select the appropriate clone from the table, click Refresh, select the desired Point In Time or Snapshot, and then click Refresh12. This process allows the developer to update the cloned database3.

According to the Nutanix Database Automation (NCP-DB) learning documents, when dealing with an Availability Group (AG) database, the database should be registered as an Availability database1. This is because the AG database is hosted on replicas with different named instances, and registering it as an Availability database allows for Copy Data Management operations to be performed across all instances. This is particularly important when services such as the Analytics service running on SQLAGN3\DW require realtime data1.

Explanation: The correct answer is B because the Time Machine feature of NDB collects logs and snapshots from databases and stores them in a distributed file system. The Time Machine enables the administrator to protect, clone, and restore databases using the SLA policies and the NDB UI or API. The Time Machine also manages the replication of database snapshots in an NDB multicluster environment. The other options are not correct because they describe different features or functions of NDB. Option A is not correct because Database Restore is an operation that uses the Time Machine to restore a source database or a clone to a previous point in time. Option C is not correct because SLA is a policy that defines the frequency and retention of database snapshots and logs. Option D is not correct because One-click Patching is a feature that allows the administrator to test, publish, and apply database patches using the NDB UI or API.

Explanation:
NDB SLAs are service level agreements that define the data protection and recovery objectives for NDBmanaged databases. NDB SLAs consist of data retention policies that specify how long the snapshots and log backups of a database are kept in the Time Machine. Data retention policies can be customized to meet different business and compliance requirements, such as daily, weekly, monthly, or yearly retention periods. NDB SLAs also determine the frequency and schedule of the snapshots and log backups, as well as the storage location and replication options. An administrator who is tasked with auditing NDB SLAs will be reviewing the data retention policies of each database and Time Machine, as well as the snapshot and log backup history and status. The administrator will also be able to monitor the storage usage and performance of the NDB SLAs, and modify or delete the SLAs as needed. The other options are not part of the NDB SLAs, but rather separate features or concepts of NDB. Snapshot schedules are the intervals at which NDB takes snapshots of the databases, which are determined by the SLAs. Clone management is the process of creating, refreshing, or deleting database clones from the Time Machine. Recovery time objective (RTO) is the maximum acceptable time for restoring a database after a failure, which is influenced by the SLAs, but not defined by them.