20 VSAN Interview Questions and Answers

Virtual SAN, or VSAN, is a software-defined storage solution that is often used in enterprise environments. If you are interviewing for a position that involves VSAN, it is likely that the interviewer will ask you questions about your experience and knowledge of the product. In this article, we review some of the most common VSAN interview questions and provide tips on how to answer them.

VSAN Interview Questions and Answers

Here are 20 commonly asked VSAN interview questions and answers to prepare you for your interview:

1. What is Virtual SAN?

Virtual SAN, or VSAN, is a software-defined storage solution that is designed to provide storage for virtual machines in a vSphere environment. VSAN aggregates local storage devices from multiple ESXi hosts and presents them as a single storage pool that can be used by virtual machines.

2. What are the advantages of using VSAN over other storage solutions like NetApp, EMC VNX, and HP 3PAR?

There are several advantages of using VSAN over other storage solutions:

1. VSAN is much simpler to deploy and manage than other storage solutions, since it is a software-defined solution that runs on top of existing server hardware.

2. VSAN is highly scalable and can be easily expanded by adding more nodes to the cluster.

3. VSAN provides excellent performance thanks to its use of flash storage and intelligent caching algorithms.

4. VSAN is very cost-effective, since it does not require the purchase of expensive proprietary hardware.

3. What types of data can be stored in a virtual SAN?

A virtual SAN can store any type of data, but it is often used to store virtual machine images or other large files.

4. Can you explain what hybrid vsan is? How does it work?

Hybrid vsan is a type of storage area network that uses both traditional hard disk drives and solid state drives. The solid state drives are used for caching, while the hard disk drives are used for storing data. The advantage of this type of vsan is that it can provide the speed of solid state drives while still offering the storage capacity of hard disk drives.

5. What are some use cases for virtual SAN?

There are many potential use cases for virtual SAN, as the technology can be used to provide storage for a variety of different applications. Some common use cases include virtual desktop infrastructure, server virtualization, and cloud computing.

6. What hardware components do I need to set up a VSAN cluster?

In order to set up a VSAN cluster, you will need a minimum of 3 servers, each with at least 1 disk controller and 2 hard drives.

7. What’s the minimum number of nodes required to create a VSAN cluster?

The minimum number of nodes required to create a VSAN cluster is three.

8. Is there any way to increase the performance of a VSAN network with more than two NICs connected? If yes, then how?

There are a few ways that you can increase the performance of a VSAN network with more than two NICs connected. One way is to use link aggregation, which will combine the bandwidth of multiple NICs and provide a single, high-speed connection. Another way is to use jumbo frames, which are larger than standard Ethernet frames and can therefore carry more data. Finally, you can use Quality of Service (QoS) to prioritize traffic on the network and ensure that mission-critical data is always given priority.

9. What happens if one of my hosts fails while running on a VSAN network?

If one of your hosts fails while running on a VSAN network, the other hosts in the network will continue to operate as normal. The failed host will be automatically removed from the network, and the other hosts will continue to communicate with each other and share data as usual.

10. What is a cache device? Why is it needed?

A cache device is a type of storage device that is used to improve the performance of a computer or other type of system by storing frequently accessed data in a location that can be accessed more quickly than other types of storage. Cache devices are often used in conjunction with other types of storage devices, such as hard drives or solid state drives, in order to provide the best possible performance for a given system.

11. What is a witness appliance and why is it important?

A witness appliance is a small virtual machine that is used to provide quorum in a two-node VSAN deployment. Without a witness appliance, it would not be possible to have a quorum and the VSAN would not be able to function.

12. What is the recommended size for witness appliances?

The recommended size for witness appliances is 3GB.

13. Where should the witness appliance be installed in context with a VSAN network?

The witness appliance should be installed in a location that is physically separate from the other nodes in the VSAN network. This ensures that if there is a failure at one location, the witness appliance will still be available to keep the VSAN network running.

14. What is the maximum number of disks allowed per host in a VSAN cluster?

The maximum number of disks allowed per host in a VSAN cluster is 32.

15. What is the max number of single-disk failures that can be tolerated by a five-node VSAN cluster?

A five-node VSAN cluster can tolerate a maximum of two single-disk failures.

16. What is the most efficient way to check if a particular mount point supports XFS format or not?

The most efficient way to check if a particular mount point supports XFS format or not is to use the “file -s” command. This command will give you information about the type of file system that is present on the mount point.

17. What are the different ways to monitor the health of a VSAN cluster?

There are a few different ways that you can monitor the health of a VSAN cluster. The first is by using the vSphere web client. You can also use the VSAN Health service, or the VSAN Observer tool.

18. What factors affect the performance of a VSAN cluster?

There are a few factors that can affect the performance of a VSAN cluster. One is the number of disks that are being used in the cluster. The more disks that are being used, the more I/O operations that can be performed in parallel, and the better the performance will be. Another factor is the type of disks that are being used. SSDs will generally provide better performance than HDDs. Finally, the configuration of the cluster can also affect performance. For example, if the cluster is not properly balanced, then some nodes may be overloaded while others are underutilized, which can lead to poor performance.

19. What are the various metrics used to measure the performance of a VSAN network?

There are a few different metrics that can be used to measure the performance of a VSAN network. These include things like IOPS, latency, and throughput. By monitoring these metrics, you can get a good idea of how well your VSAN network is performing and make adjustments as needed to ensure that it is running smoothly.

20. What are the best practices for managing and optimizing a VSAN network?

There are a few key things to keep in mind when managing a VSAN network:

– Make sure that you have enough disk space to accommodate the data you plan to store on the network.

– Balance the load across the different nodes in the network to ensure optimal performance.

– Keep an eye on the network traffic to ensure that it is not becoming overloaded.