Oracle Real Application Clusters (RAC) is an enterprise database solution offering high availability and scalability to mission-critical applications, offering superior application performance at scale. As its popularity continues to increase, interviews for database administrator (DBA), DBA/DBA roles, or related positions featuring Oracle RAC become more common.

To help prepare you for such interviews we present frequently asked interview questions related to this subject that should help make you confident during an interview process involving this technology solution.

In this blog post,interview questions on OracleRAC these questions to give you an advantage during any such interviews or related roles focused on Oracle Real Application Clusters (RAC).

1.What are the components of each node in RAC Architecture?

The components of each node include DB instances, ASM, JPAO node membership, and the OS.

2.Define the H Factor and the starting sequence for services in RAC Architecture?

The H Factor is a concept in RAC Architecture, and the starting sequence for services refers to the order in which services start-up in a RAC cluster.

3.What are local registry and cluster registry in RAC Architecture?

Local registry and cluster registry are resources that reside on specific nodes and are only applicable within them. Some services are responsible for decluttering and switching to surviving nodes if a node goes down.

4.How is the data architecture connected to the front end in RAC Architecture?

The data architecture is connected to the front end via app servers, web servers, or other applications using three-tier methods.

5.Define the role of VIP and scan IP in RAC Architecture?

VIP and scan IP are used to ensure that applications can establish connections to the database even if a physical IP goes down.

6.List out the difference between a public and private subnet in RAC Architecture?

The public subnet is used for external communication, while the private subnet is used for internal communication within the rack.

7.What is a virtual IP address (VIP) in RAC Architecture?

A virtual IP address (VIP) is a logical IP address that can be used to connect to the database instead of a physical IP address.

8.What happens if an application connects to a different node in RAC Architecture?

If an application connects to a different node, the connection will be lost, and the application will need to connect to a VIP instead to avoid this scenario.

9.Define a CHF framework in RAC Architecture?

A CHF framework is used to shift the VIP node to a surviving node in case of node failure, ensuring that the rack connection is handed over to the existing or surviving node.

10.Why is the VIP concept important in RAC Architecture?

The VIP concept is important because it allows for the rack connection to be handed over to the existing or surviving node in case of node failure, ensuring high availability and reliability.

11.What is the role of database listeners in RAC Architecture?

Database listeners usually listen under VIP addresses, but if a node goes down, the client needs to switch over their connections to maintain availability.

12.Describe what is Oracle Rack and how does it differ from other Oracle architectures?

Oracle Rack is an Oracle Real Application Cluster that allows multiple instances to access a single database using Oracle Grid architecture for high availability and scalability. It differs from other architectures as it allows for increased user connections and efficient database management.

13.List out the benefits of having a separate subnet for physical nodes, virtual IPs, and scan VIPs?

Having separate subnets for physical nodes, virtual IPs, and scan VIPs can improve security, simplify network management, and prevent potential IP address conflicts.

14.What are the advantages of having a scan over a VIP, and vice versa?

Having a scan provides greater flexibility and allows for easier addition or removal of nodes, while a VIP provides a consistent IP address for a specific service.

15.Can physical IPs, virtual IPs, and scan IPs be in different subnets?

Yes, but it is important to consider the potential implications and ensure proper network configuration.

16.List the components of Oracle Rack and their functions?

Oracle Rack includes shared and dedicated database components, such as shared storage areas like NASOS and online redo log files, dedicated memory components like the SGA, and essential components for managing data-based clients like ATL Clusterware and ASM Volume Manager.

17.Tell about RACand what are its primary uses?

RAC is a clustering solution that combines RAC with a data guard to provide high availability at the site level. It is primarily meant for use on the same site, ensuring node failure protection. RAC is a highly scalable clustering technology that can be used with containers like Docker, SQL, and is available in Oracle OCI Cloud, Oracle, ASM, and Exadata.

18.List out the benefits of using RAC over a single database instance architecture?

RAC provides redundancy and higher availability by using groups of ASM. It also allows for online operations, data relocation, and server switchovers. RAC is more expensive than a single database instance license, but it offers higher performance benefits.

19.What is the minimum configuration required for the Oracle Rack training?

The minimum configuration required for the Oracle Rack training is 16GB RAM and around 100GB hard disk for virtual machines or 150GB hard disk for the host.

20.Describe what is a rack application cluster and how does it ensure high availability?

A rack application cluster is a multi-level instance architecture that creates multiple instances on top of three hosts, ensuring high availability by using shared storage and the cost of having three hosts.

21.Mention the difference between a RAC one node and a full RAC license?

A RAC one node is a cheaper option that offers a single instance license, while a full RAC license is the most costly option that provides more robust features and benefits.

22.What are the benefits of using RAC over other clustering solutions like AWS IDB?

RAC offers rolling patching, which allows one node to be patched at a time without downtime, and it supports various storage solutions like Oracle, ASM, and Exadata. It also provides higher availability and performance benefits.

23.Can RAC be used for separate configurations like D-Bass?

Yes, RAC can be used for separate configurations like D-Bass, which is an equivalent to AWS IDB.

24.How can one refresh and wrap from L0, L1 backup in R A C?

To refresh and wrap from L0, L1 backup in R A C, synchronization is required, and all local and shared backups must be accessible by the node performing the refresh.

25.What topics can be covered in the Oracle Rack training program?

The Oracle Rack training program can cover the topics such as grid infrastructure management, cluster management, CRS, CTL, SLV, CTL commands, working with OCR, voting disks, OLR, demons, architecture, creating RAC databases, monitoring, tuning, AWS, failovers, TAF, and FAN configuration.

26.What is the process of upgrading grid infrastructure in RAC?

Upgrading grid infrastructure in RAC requires the correct bundle of steps, but it is not a difficult process.

27.Define the main component of a cluster?

The main component of a cluster is the cluster nodes, which are single machines that participate in the cluster.

28.What software manages the workload and distributes incoming connections to the nodes in a cluster?

The cluster software manages the workload and distributes incoming connections to the nodes in a cluster.

29.Give definition What is node eviction in a cluster?

Node eviction refers to when nodes leave the cluster, and the cluster software restarts and joins them back into the cluster.

30.How does a cluster communicate with its nodes?

A cluster communicates with its nodes using a single name without providing any IP address or local or physical name of each node.

31.What is the role of shared storage in a cluster?

Shared storage is a crucial component of a cluster as it removes single node dependency and ensures that all nodes can access the files.

32.Name the two networks required for Oracle RAC?

Oracle RAC requires only two networks: one public and one private network.

33.What software manages redundancy and administers storage disks and disk groups in Oracle RAC?

Oracle RAC manages redundancy and administers storage disks and disk groups using Oracle RAC.

34.What is a cluster and how does it manage data within a large network?

A cluster is a powerful tool for managing and managing data within a large network. It allows for easy addition and removal of nodes, manages redundancy, and ensures efficient communication between nodes.

35.Name thesoftware do you need to install to create a cluster?

To create a cluster, you must install the grids software and Oracle home on each node.

36.Describe What is the role of the cluster software in a cluster?

The cluster software manages the workload and distributes incoming connections to the nodes in a cluster and provides high availability by checking with every possible node and executing requests on the 10th node.

37.What is the RAC (Real Application Cluster) software used for in the Oracle database environment?

The RAC software is used for clustering and high availability in the Oracle database environment.

38.When was the RAC introduced and what versions of Oracle did it come with?

The RAC was introduced in code-transcendo-1 with Orec and 9i.

39.Who provides RAC in the standard and Android additions?

Oracle Group provides RAC in the standard addition, and it comes with extra cost in the Android addition.

40.How do multiple instances communicate in the RAC environment?

Multiple instances communicate with a single database, running on separate machines and servers.

41.What is the shared area between all RAC nodes used for?

The shared area between all RAC nodes is where data is stored and resources manage data.

42.List the main objectives of RAC configurations?

The main objectives of RAC configurations are to provide performance scalability and resilience, with high availability, reliability, scalability, manageability, reliability, transparency, role locking, error detection, buffer cache management, load balancing, sharing, and reductions in total cost.

43.What are the three types of IP addresses in the RAC environment?

The three types of IP addresses are public, private, virtual, SCN, and SCN.

44.Why is Oracle RAC crucial for highly available environments?

Oracle RAC is crucial for highly available environments, especially for those working on databases or upgrading to R A C.

45.What is the concept of a cluster in the context of Oracle R A C?

A cluster refers to a group of interconnected nodes acting as a single system, and it is essential for applications that want to be highly available and are deployed in clusters, even in cloud environments.

46.Define what is Oracle Rack and how is it managed?

Oracle Rack is a real application cluster that comprises multiple interconnector servers that appear as one server to run applications. It is managed using clusterware software.

47.How many instances can one rack database have?

One rack database can have up to 100 instances.

48.What is the difference between Oracle RAC and distributed data?

There is no difference between RAC and distributed data, as RAC is a clustered environment.

49.Is it recommended to take the D B A course before pursuing the Oracle RAC course?

Yes, it is recommended to take the D B A course before pursuing the Oracle RAC course, as it is directly related to clustering.

50.What is Data Guard and how does it relate to Oracle?

Data Guard is a feature in Oracle that provides disaster recovery solutions.

51.What is ASM and why is it a prerequisite for understanding Oracle Rack?

ASM is a storage solution built on top of A S M, and it is a prerequisite for understanding Oracle Rack.

52.Tell about thethe role of Google Net Services client access in Oracle RAC?

Google Net Services client access is used to distribute connection requests across multiple instances in Oracle R A C.

53.What are the advantages of distribution in Oracle RAC?

The advantages of distribution in Oracle RAC include allowing a single load to not be loaded with too many connection requests and allowing three instances to serve in parallel.

54.What is the role of ASM and ASM Volume Manager in managing data-based clients in a multi-node cluster environment?

ASM and ASM Volume Manager are essential components for managing data-based clients in a multi-node cluster environment, optimizing database management, and reducing the need for Oracle ASM portraver or other systems.

55.What is Oracle Flex ASM and what are its benefits?

Oracle Flex ASM is a feature that allows for managing Oracle ASM instances on separate physical servers, supporting larger cluster setups, and reducing Oracle ASM portrayer or other systems.

56.Why is it important to create a separate ATL home on each instance when installing Oracle Rack?

Creating a separate ATL home on each instance allows for better management advantages, out-of-place patching, and eliminating database downtime in multi-node cluster environments.

57.What are the key benefits of using Oracle Rack for high availability and scalability?

Oracle Rack allows for increased user connections, efficient database management, and improved performance, as well as the ability to add additional nodes for increased capacity without requiring any application changes.

58.What benefits does Oracle Clusterware architecture offer?

Oracle Clusterware architecture offers benefits such as reduced system contention and loads, improved scalability, reduced costs on security infrastructure management, and low-cost hardware.

It also allows for more scalable applications, the ability to fail over nodes, increased throughput on demand, and the ability to monitor and restart processes.

Data centre server roomThe ASM CMD utility is used to check flex mode and cluster mode in Oracle Clusterware.

59.What utility allows for checking flex mode and cluster mode in Oracle Clusterware?

The ASM CMD utility is used to check flex mode and cluster mode in Oracle Clusterware.

60.What are cluster underscore interconnect parameters?

Cluster underscore interconnect parameters can be used to override default interconnects with preferred traffic networks.

Conclusion:

Oracle Rac interview questions and answersplay an essential part of hiring processes at many organizations. Preparation for them requires having a solid grasp on its technology, features, components and their interactions – practicing common Oracle racscenario-based interview questions will allow you to confidently address queries regarding high availability solutions such as scaling capacity clustering or backup solutions from Oracle RAC technology.

Hope the oracle rac interview questions and answers for experiencedin this blog post have provided useful insight and prepared you for an Oracle RAC interview.