What is VMware vSAN? All the tricks you need to know

VMware vSAN is the storage solution your virtualized environment has been missing. We understand the frustration of dealing with clunky storage arrays and sluggish performance. It’s like trying to fit a square peg into a round hole when you’ve tried to scale. 

Imagine the relief and satisfaction your teams and users would feel if you could bid farewell to those storage headaches and welcome a hyper-converged infrastructure that works. With VMware vSAN, you can. 

In this article, we’ll empower you to get the most out of your virtualized environment with vSAN, from setup to optimization.

• What is VMware vSAN? What does it do?
• Benefits of VMware vSAN for your business
• What are the key features of VMware vSAN?
• Architecture and components of vSAN
• How to set up and configure VMware vSAN
• 7 tips for getting the most out of VMware vSAN
• Common issues with VMware vSAN and troubleshooting strategies
• Common scenarios for vSAN deployment
• VMware vSAN vs. SAN
• FAQ on VMware vSAN
• Getting started with VMware vSAN – what you need to know
• Streamline your vSAN investment with Liquid Web

What is VMware vSAN? What does it do?

VMware vSAN is a software-defined storage solution that enables the creation of a highly available and scalable storage infrastructure for virtualized environments. With vSAN, the storage capacity of multiple ESXi hosts is aggregated into a single storage pool that the vCenter Server can manage centrally. This efficient setup eliminates the need for a dedicated external storage array, potentially reducing costs and simplifying deployment and management.

vSAN’s primary goal isn’t just to streamline storage provisioning and management for virtual machines but to do so with a robust infrastructure designed to withstand failures. It provides a reliable backbone for your virtualized environment, ensuring continuity even in the face of challenges.

Also, vSAN includes comprehensive data protection features, such as RAID-1 mirroring, RAID-5/6 erasure coding, and stretched clusters, which enhance fault tolerance and significantly reduce the risk of data loss.

Now that we’ve briefly explored how VMware vSAN works, let’s focus on what matters: its benefits for your business.

Benefits of VMware vSAN

When you implement vSAN, you equip your data center with benefits that transform your storage infrastructure and streamline business operations.

Scalability

vSAN provides a highly scalable storage infrastructure that can easily scale up or down as your business needs vary. For instance, if your company experiences a sudden surge in demand, you can quickly scale up your storage capacity to meet the increased workload. 

Conversely, vSAN makes it easy to scale down without disrupting your operations if you need to reduce storage resources. This flexibility is valuable for businesses with fluctuating workloads or those experiencing rapid growth.

Resiliency

VMware vSAN is designed to provide high availability and resiliency for virtualized workloads. It provides advanced data protection features, such as RAID and erasure coding, that minimize failure and downtime. For example, if a disk fails, vSAN can automatically repair the failed component, ensuring data availability and minimizing the impact on your business.

Reduced costs

Since vSAN uses the local storage resources of ESXi hosts, it eliminates the need for dedicated storage hardware. This reduces costs and simplifies deployment. It also provides efficient data compression and deduplication, which can help reduce storage costs.

Simplified management

vSAN is fully integrated with VMware vSphere, enabling centralized virtual machine management and storage resources. Ultimately, this simplifies management and improves efficiency while ensuring advanced automation capabilities through vSphere application programming interfaces (APIs).

A cloud service provider can use vSAN to simplify customer storage management, providing a self-service portal for easy provisioning and management of storage resources.

Better support for modern applications

Modern-day applications require access to scalable storage to deal with the dynamic workloads that users throw at them. vSAN provides better support for modern applications, such as containerized workloads and big data analytics. With vSAN, businesses can easily deploy and manage modern applications in virtualized environments.

A good example is a tech startup that develops AI-driven applications that can use vSAN to deploy and manage the necessary storage resources quickly for its data-intensive projects. This enables rapid innovation and supports the company’s growth.

What are the key features of VMware vSAN?

Having understood the benefits vSAN can offer your business, you’re probably wondering what makes this solution special. Buckle up as we dive into the key features that make vSAN a game-changer.

Storage Policy Based Management (SPBM)

SPBM enables administrators to create and enforce storage policies. These policies automate provisioning and assign performance levels, availability, and redundancy to virtual machines (VMs) based on specific requirements, directly impacting your daily operations.

Deduplication and compression

vSAN’s deduplication and compression capabilities reduce storage consumption by eliminating redundant data and compressing stored information. This optimization leads to substantial space savings and improved storage efficiency.

Stretched clusters

Stretched clusters, a testament to vSAN’s reliability, provide high availability and disaster recovery capabilities. By extending a single vSAN cluster across multiple geographic sites, this system ensures that even if one site experiences a failure, your data is replicated and remains accessible. You can trust vSAN’s resilience to keep your data secure.

Data encryption

vSAN encrypts data as it writes it to disk, protecting sensitive information from unauthorized access and ensuring data security at rest.

Architecture and components of vSAN

Its robust architecture and components are at the core of VMware vSAN’s magic. Let’s examine the details to understand what makes this solution tick.

Disk groups 

Disk groups form the foundation of vSAN’s storage architecture. They’re a collection of physical disks or drives the hosts contribute to a vSAN cluster. The system divides these disk groups into cache and capacity tiers, using different disk types to optimize performance and storage efficiency. 

vSAN supports two primary disk group configurations: hybrid, which combines high-performance SSDs for caching with cost-effective HDDs for capacity, and all-flash, which exclusively uses SSDs for both caching and capacity tiers. This flexibility allows businesses to tailor their storage infrastructure based on specific performance and cost requirements.

Cache tier 

The cache tier is the secret sauce behind vSAN’s exceptional performance. It employs low-latency, high-performance devices like SSDs or NVMe drives to accelerate read and write operations. By serving as a caching layer, the cache tier ensures that frequently accessed data is readily available, minimizing latency and boosting overall system responsiveness. 

vSAN intelligently manages the cache tier, automatically promoting and demoting data based on usage patterns to optimize cache utilization. This results in a seamless and efficient storage experience for applications and end-users.

Capacity tier 

While the cache tier focuses on performance, the capacity tier is all about storage capacity. It uses higher-capacity devices, such as HDDs or lower-endurance SSDs, to provide the bulk of the storage space for the vSAN cluster. 

The capacity tier is where most of the data resides. It’s designed to offer cost-effective storage at scale. To ensure data protection and resilience, vSAN employs mirroring or erasure coding across the capacity tier. 

Mirroring creates multiple copies of data across different hosts, providing redundancy in case of disk or host failures. Erasure coding breaks data into smaller fragments and distributes them across multiple hosts, allowing for efficient data reconstruction during failures.

Network 

The network is the glue that holds the vSAN cluster together. It enables seamless host communication, allowing them to collaborate and share storage resources effectively. 

vSAN requires a high-bandwidth, low-latency network infrastructure to ensure optimal performance and minimal latency. Remote Direct Memory Access (RDMA) networks like [InfiniBand], commonly used in high-performance computing, and 10 Gigabit Ethernet (10GbE), a standard for high-speed Ethernet, are examples of such networks. 

It also incorporates network partitioning and fault tolerance mechanisms to maintain data availability and integrity even during network disruptions or failures.

vSAN witness 

When a vSAN cluster spans multiple sites or data centers, the vSAN witness plays an important role in maintaining data consistency and preventing split-brain scenarios. A split brain occurs when nodes in a cluster become disconnected and start operating independently, leading to data inconsistencies. 

The vSAN witness acts as a tiebreaker, helping the cluster maintain quorum and data integrity. It can be deployed as a host-based witness, on a separate vSAN host, or as an external witness appliance. 

The witness communicates with the vSAN nodes to monitor their status and make decisions based on predefined policies. This ensures data remains consistent and accessible during site failures or network partitions.

How to set up and configure VMware vSAN

Excited to experience the power of vSAN for yourself? Don’t worry. We’ve got you covered. These are the typical steps you will have to implement when setting up and configuring VMware vSAN.

Step 1: Determine hardware and software requirements

Ensure your hardware and software meet the minimum requirements for vSAN. This includes compatible hardware, such as solid-state drives (SSDs) or the modern nonvolatile memory express (NVMe) drives, and supported versions of vSphere and vCenter Server.

Don’t forget to verify specific hardware requirements for your servers and components and check you have the minimum number of hosts required for vSAN.

Step 2: vSAN network configuration

Configuring the vSAN network enables proper communication between ESXi hosts in the cluster. You can configure the network using dedicated physical or virtual network adapters.

Address network requirements like NIC configuration and redundancy, as well as virtual networking details such as VMkernel adapters, virtual switches, and network partitioning/fault tolerance. A well-configured network is key to a smooth vSAN experience.

Step 3: VMware vSAN licensing

There are three options for licensing VMware vSAN: per CPU, per concurrent user in 10- or 100-license packs for virtual desktop infrastructure (VDI), or per virtual machine (VM). Choose the one that best fits your organization’s requirements and budget.

Step 4: Create and enable cluster creation

Add the ESXi hosts to your vSphere environment to create a vSAN cluster. Enable vSAN on the cluster and perform basic configuration, including setting up disk groups as either hybrid or all-flash to match your hardware capabilities. Ensure your network infrastructure supports high-speed, low-latency connectivity to minimize problems. 

Step 5: vSAN storage configuration

After creating the vSAN cluster, configure storage policies to define how data is managed. Create new vSAN storage policies in the vSphere Client, defining requirements such as failure tolerance method (RAID-1, RAID-5/6), number of failures to tolerate, and object space reservation. 

Choose appropriate RAID configurations based on your performance and redundancy needs: RAID 5 for balanced performance and protection or RAID 6 for higher fault tolerance.

Set advanced policy rules, such as cache reservation or encryption, if needed. Configure cache tiering and implement deduplication and compression for space efficiency. Assign these policies to virtual machines and virtual disks.

Ensure that your network infrastructure supports high-speed, low-latency connectivity to minimize bottlenecks. Implement deduplication and compression for space efficiency, and monitor key performance metrics like IOPS and latency to ensure your vSAN is running at its best.

Step 6: Monitoring, maintenance, and management

You can use the vCenter Server console or other management tools to manage and monitor your vSAN’s cluster health and storage resources and perform routine maintenance tasks. Remember to set up regular backups and restore procedures to protect your data. 

Use performance charts and alerts to proactively manage potential issues, and consider third-party solutions for enhanced monitoring and management capabilities, such as Veeam ONE for comprehensive monitoring and analytics, or explore managed hosting providers like Liquid Web, which offers expertise in vSAN environments. 

Perform routine maintenance tasks, including regular health checks, firmware updates, and disk maintenance. Set up regular backups and restore procedures to protect your data. This ongoing management will help ensure the smooth operation of your vSAN environment.

Step 7: Configure advanced settings (optional)

If you’re looking to take their vSAN to the next level, you should consider configuring advanced settings.

• Set up a vSAN witness to maintain a quorum in stretched clusters.
• Define fault domains for rack awareness and host groups to improve resilience.
• Enable vSAN encryption for an additional layer of security.
• Fine-tune advanced settings like object repair timer and site read locality for stretched clusters.

With these steps, you’ll be well on your way to harnessing VMware vSAN’s power in your organization.

7 tips for getting the most out of VMware vSAN

Here are some of the tested strategies you can use to get the most out of your VMware vSAN.

1. Properly size your vSAN cluster

This is essential for achieving optimal performance and capacity.

2. Use cutting-edge hardware

vSAN can use the latest storage technologies, such as flash-based SSDs and NVMe drives, to deliver high-performance and low-latency storage.

3. Use vSAN storage policies

Using vSAN storage policies ensures that virtual machines are stored efficiently and with the appropriate levels of protection and performance.

4. Enable deduplication and compression

This can reduce storage costs and improve performance by reducing the amount of data that needs to be stored.

5. Optimize cache tiering

You can optimize cache tiering by ensuring that you have enough cache capacity and by configuring the cache reservation settings appropriately. Proper cache configuration accelerates read and write operations, improving overall storage responsiveness.

6. Maintain data integrity and resource availability

When dealing with hyper-converged infrastructure (HCI) powered by vSAN, rebooting hosts can be high risk if not executed properly. Taking a host offline during hardware replacements by simply rebooting affects the entire cluster’s compute and storage resources, potentially leading to service disruptions and data integrity issues.

Offline mode can disrupt your cluster’s computing and storage capabilities, which you want to avoid. Rebooting hosts in a vSAN cluster needs to be done carefully to prevent disruptions to your workloads.

7. Use VDS for vSAN optimization

A key feature to consider when using vSphere Distributed Switch is the Network I/O Control (NIOC). This feature ensures that vSAN always receives the necessary bandwidth, even when shared network interfaces are used, by providing traffic-shaping capabilities.

Common issues with VMware vSAN and troubleshooting strategies

Like any technology, VMware vSAN may encounter issues. However, we can assist you with troubleshooting and resolving challenges related to your vSAN environment. Let’s explore some common issues and effective strategies to address them.

Disk group degradation

vSAN uses disk groups to provide redundancy and ensure data availability. If a disk group degrades, it can lead to a loss of redundancy and impact data availability. To troubleshoot disk group degradation, check the health of each disk and replace any failing components. You must also check for network or hardware issues impacting the disk group.

Slow performance

Sluggish vSAN performance can negatively affect application performance and user experience. Common contributing factors include network latency, insufficient hardware resources, and misconfigured storage policies. To troubleshoot slow performance, review the vSAN performance metrics, optimize the cache tier, and ensure that hardware resources are adequate for the workload.

Network connectivity issues

vSAN requires a stable and reliable network connection between hosts in the cluster for optimal performance. Network connectivity issues can result in data unavailability and degraded performance, potentially impacting your operations. Troubleshoot network connectivity issues by checking network settings, reviewing logs, and ensuring that firewalls and other security measures are not interfering with network traffic.

Disk capacity issues

Running out of disk space can lead to data unavailability and a drop in performance. To troubleshoot disk capacity issues, review storage policies, and reclaim space where possible. Additionally, identify oversized or unnecessary virtual machines and add more disk capacity to the cluster.

Cluster health issues

Issues related to cluster health can also contribute to problems with data availability and degraded performance. To troubleshoot cluster health issues, review the vSAN health and performance metrics, check host health and configuration, and ensure that all software components are up-to-date and compatible.

Common scenarios for vSAN deployment

Here are some of the most typical use cases where vSAN deployment can make a significant impact.

Virtual desktop infrastructure (VDI)

VMware vSAN, in combination with VMware Horizon, provides an effective solution for VDI deployments. vSAN’s native file services simplify the management overhead of providing file-level services in VDI environments. 

Instead of relying on legacy physical storage arrays or deploying additional VMs and licenses, administrators can enable file services at the cluster level on a vSAN cluster.

VMware Horizon supports desktop and application models, including nonpersistent desktops with persistent user experiences. Non-persistent VMs significantly improve the speed and efficiency of desktop and application lifecycle management.

Disaster recovery and business continuity

The financial impact of system failures has intensified. In 2022, incidents costing more than $1 million grew from 11 percent to 15 percent, highlighting the increasing severity of downtime on businesses.

Protect your business from the escalating financial impact of system failures with vSAN’s robust disaster recovery solution, built on a powerful HCI foundation. By integrating with the vSphere, vSAN simplifies storage management through policy-based automation, ensuring rapid recovery and minimal RTOs during disasters. This not only saves you from potential losses but also provides a sense of security and reassurance. 

Keep your mission-critical workloads, like websites, databases, and applications, running smoothly with shared storage and automatic failover capabilities. 

vSphere Replication works seamlessly with the Site Recovery Manager to orchestrate DR processes, including precise startup orders and IP changes, giving you peace of mind. Plus, vSAN’s proactive monitoring helps you stay ahead of potential issues and scale effortlessly as your business grows.

Remote office/branch office (ROBO)

Another use case of vSAN is ROBO deployments, where a cost-effective and scalable storage solution is essential. With vSAN’s hyper-converged architecture, organizations can deploy compact, all-in-one solutions that combine compute and storage resources in a single node. This approach reduces the need for separate storage arrays and simplifies management in remote locations with limited IT staff.

Thanks to vSAN’s centralized management and monitoring capabilities, IT teams can easily manage multiple ROBO deployments from a single, unified interface. This centralized control reduces the administrative overhead associated with managing distributed infrastructure. It also ensures that remote offices receive the same level of storage performance and data protection as the primary data center.

VMware vSAN vs. SAN

Now that we’ve covered the basics of VMware vSAN, you might wonder how it stacks up against traditional storage area network (SAN) solutions. Let’s take a look at the differences between VMware vSAN and SAN.

FAQs on VMware vSAN

Learning about VMware vSAN can feel like diving into the deep end at first. That’s why we’ve compiled a handy list of common questions and answers to help you wrap your head around it.

Is vSAN software or hardware?

vSAN is a software-defined storage solution that creates a virtual storage environment using your existing hardware resources.

What is the maximum size of vSAN?

vSAN’s scalability allows you to grow your storage capacity significantly by adding more hosts to the cluster.

What type of storage is vSAN?

vSAN is a distributed, shared-nothing storage solution that pools the local storage resources of your ESXi hosts.

What is the difference between VMware ESXi and vSAN?

ESXi is the hypervisor that enables virtualization, while vSAN provides a distributed, shared-nothing storage environment for virtual machines.

How many ESXi hosts are required for vSAN?

At least three ESXi hosts are needed to create a vSAN cluster and use its data protection and availability features.

Getting started with VMware vSAN — what you need to know

Before you get started with VMware vSAN, you need a cluster of at least three hosts running one of the latest versions of VMware, plus a minimum of one flash device and one capacity device per host. vSAN is licensed separately from the VMware vSphere hypervisor and can be deployed in different ways, including as a hybrid or all-flash solution and as a two-tier architecture or stretched cluster for disaster recovery.

It should also be noted that storage policies determine how data is stored and replicated across hosts. vSAN provides tools for monitoring and managing your storage environment, including the vSphere Web Client and vSphere Client. Understanding these key concepts is essential for achieving efficient, scalable, and reliable storage for your virtualized environment with vSAN.

Streamline your vSAN investment with Liquid Web

VMware vSAN is a powerful and flexible software-defined storage solution that can help you build highly scalable, resilient, and cost-effective storage infrastructure for your virtualized environments. With vSAN, your business can easily manage storage resources, simplify deployment, and ensure high availability and performance for your virtual machines.

By following the steps outlined in this article and implementing the best practices for using vSAN, such as optimizing storage policies and leveraging deduplication and compression, you can optimize your virtualization infrastructure, improve efficiency, and reduce costs. vSAN is a valuable solution for organizations looking to maximize the benefits of virtualization technology.

The team at Liquid Web is always ready to assist you. Whether you have questions about vSAN, or need help with a VMware private cloud implementation, get in touch to experience our unwavering support.