Upgrade from vSphere 8 to a VCF 9.1 Minimal Deployment

In the vSphere 8 era, many small environments relied on the lean duo of ESXi and vCenter for simplicity and low overhead. VMware Cloud Foundation (VCF) 9.1 evolves this model into a full-stack private cloud, offering automated lifecycle management, advanced networking, native container support, application blueprint provisioning, private AI, and much more--albeit with higher resource demands.

Fortunately, a minimal VCF installation enables smaller shops to use vCenter and ESX 9.1 without overcommitting their hardware. It is important to understand that you will not get all the full-stack VCF 9.1 private cloud features and benefits when you perform a minimal installation or upgrade.

Introduction

This article summarizes the process of upgrading vSphere 8 (vCenter 8 and ESX 8) to VCF 9.1. Detailed steps are provided in the Broadcom Technical Documentation. Below are the high-level steps. Steps 1 and 2 are the biggest differences between vSphere 8.0 and a 9.1 environment. VCF Operations and a license server are new requirements with 9.1.

1. Deploy VCF Operations 9.1
2. Deploy a license server
3. Upgrade vCenter to 9.1
4. Upgrade the ESX hosts to 9.1

As a reminder, ensure name resolution and time synchronization are implemented consistently across your environment for existing systems and new VCF components. I recommend reading the release notes from start to finish before proceeding. If you are running vSAN, verify all issues in vSAN Health are resolved before proceeding.

We start with a simple, 3-node cluster running vCenter 8 Update 3, ESX 8 Update 3, and vSAN ESA.

Deploy VCF Operations

The first step is deploying VCF Operations. I located and downloaded the Operations-Appliance-9.1.0.0.25346025.ova file from the Broadcom Support Portal. The exact file name/numbers will change as newer versions are released.

The .ova deployment is similar to other appliances. I chose the "small" deployment size considering this is a 3-node environment.

After successful deployment, I pointed a web browser to the new VCF Operations appliance. I chose the Express Installation for simplicity. This option will be best for the majority of environments. The initial setup process will take several minutes.

You will see a login screen after the initial setup is completed. Log in with the username admin and the password you specified during the .ova deployment. You will need to complete a few more setup steps.

Next, we will pair the new VCF Operations instance with the existing vCenter. Click the vCenter tile on the Home page and click the Add Account button.

Specify the vCenter instance you are connecting and add the credential--username and password for vCenter, e.g., administrator@vsphere.local. The Default collector group is fine for most environment. Click the Validate Connection button. If you have vSAN, activate the connection for vSAN, as well. Then, click the Add button.

You should see a popup notification, "Please note that collection for newly created vCenter accounts does not start automatically. After saving, initiate collection by clicking the ellipsis icon next to the vCenter Account and selecting 'Start Collecting' from the menu." We will need to perform that action next.

The Integrations page should show the newly-added vCenter instance. Expand the account and click the three vertical dots. Select Start Collecting All.

The status will likely change from Stopped to Warning. This is expected. Refreshing the view after a few moments should change the status to Collecting.

Finally, you will need to register VCF Operations with the VCF Business Service console to access and manage licenses in a 9.1 environment. Detailed instructions are in the Registering VCF Operations with the VCF Business Services console documentation. Most environments will benefit from the simplicity of configuring Connected Mode. There is a Disconnected Mode option for those that require it. Click Manage at the top of the VCF Operations screen and then click Licenses & Registration.

The first step in the licensing process is deploying a license server. This is new in version 9.1. There is virtually no interaction with the license server after it is deployed. All license management is performed in VCF Operations. A unique registration key is what ties the license server to VCF Operations.

You will need to download the license server .ova file, e.g., Vcf-License-Server-9.1.0.0.25346031.ova. Note that you will need to copy and paste the Unique Registration Key into the .ova deployment wizard.

Power on the license server once it is fully deployed. Wait a few moments to ensure it has completely booted. Then, click Review License Servers. You should see the new license server. Continue following the guidance in the UI and documentation depending on whether you are using Connected Mode or Disconnected Mode.

Upgrade vCenter to 9.1

Upgrading to vCenter 9.1 is similar to previous major version upgrades. It is a two stage process involving the deployment of a new appliance and the transfer or services and data from the old appliance to the new one. I am not going to cover the vCenter upgrade assuming that you have done it before. If you need detailed steps, see the Upgrading the vCenter Appliance documentation.

Upgrade the hosts to ESX 9.1

This is also similar to previous upgrades. vSphere Lifecycle Manager (vLCM) provides a GUI-driven, automated method to upgrade hosts including vendor add-ons and additional components, e.g., a newer driver, if needed. You can also upgrade hosts using a USB drive, CD/DVD, or the command line using ESXCLI. Start here if you need instructions: Overview of the ESX Host Upgrade Process.

vSAN

If you are running vSAN, it is likely you will need to update the disk format version. You will see a banner like the one shown below and vSAN Health will warn you, as well.

This is not a disruptive update, but it is always best to wait until a maintenance window or after normal business hours. Go to vSAN Health locate the Disk format version health check, and click the Troubleshoot button. Then click the Upgrade On-disk Format button. This is required to support some of the latest features of vSAN in VCF 9.1.

You might also see a health check warning about "vSAN optimal datastore default policy configuration." Click the Troubleshoot button to resolve that, as well. It is an excellent new feature that makes vSAN even easier to manage. You can read about it in this blog article: Auto-RAID in VMware vSAN for VCF 9.1 – Comprehensive System-Managed Data Resilience.

Conclusion

As mentioned previously, this minimal deployment provides a way to upgrade to 9.1 without the resource consumption of a full-stack VCF deployment. However, you miss out on many of the features and benefits of VCF. The good news is you can add components, as needed. For example, VCF Operations for Networks provides better visibility into your network infrastructure and can be added at a later time. A complete list of the VCF components including a brief description of their capabilities can be found here: Components in VCF and vSphere Foundation.

Why vSAN is Best for VMware Cloud Foundation

For VMware practitioners, the shift from traditional three-tier architectures to a software-defined data center (SDDC) isn't just about consolidation—it’s about regaining control. At the heart of this evolution is VMware vSAN, the native storage engine for VMware Cloud Foundation (VCF).  vSAN is the only option that delivers a full-stack, automated experience from Day 0 through Day 2 and it is included with your VCF subscription. Here is why vSAN remains the gold standard for VCF deployments.

The Power of "In-Kernel" Integration

Unlike external storage arrays that require separate management planes and complex fiber channel zoning, vSAN is embedded directly into the vSphere hypervisor.

• Minimized Latency: By residing within the hypervisor, vSAN eliminates the need to traverse separate storage networks, bringing data closer to the virtual machines (VMs).
• Unified Management: Manage both compute and storage through the familiar vSphere Client, significantly reducing the learning curve and administrative overhead.
• Feature Synergy: vSAN works seamlessly with core vSphere features like vMotion, DRS, and High Availability (HA) to ensure seamless workload mobility and resilience.
• Native vSAN-to-vSAN Replication:Replicate VMs between clusters using native workflows, eliminating the need for third-party replication tools for disaster recovery.

Performance: From OSA to ESA

With the maturity of the vSAN Express Storage Architecture (ESA), the performance gap between software-defined and proprietary hardware has effectively closed.

• NVMe Optimization: vSAN ESA is specifically designed for high-performance NVMe storage, utilizing a patented log-structured file system that optimizes writes.
• Adaptive Resynchronization: To maintain uptime, vSAN "self-heals" data after hardware failures, dynamically prioritizing VM traffic over background resynchronization tasks to ensure zero performance impact.
• Global Deduplication: vSAN ESA identifies and removes redundant 4KB blocks across the entire cluster rather than within a disk group, improving storage efficiency and reducing costs. Deduplication is background process, which avoids a performance impact to the write path.

Streamlined Lifecycle Management (vLCM)

Perhaps the most significant "quality of life" improvement for administrators is vSphere Lifecycle Manager (vLCM) integration.

• Full-Stack Patching: vLCM manages the entire stack—ESXi, vSAN, and the underlying hardware firmware and BIOS—ensuring a consistent, validated state across the cluster.
• Configuration Drift Control: Define a desired state for the cluster, and vLCM remediates deviations, reducing the risk of security vulnerabilities and instability.
• One-Click Site Maintenance: vSAN 9 introduces a Site Maintenance Mode for stretched clusters, allowing administrators to place a site into maintenance with a single click.

The Verdict

vSAN isn't just another storage option—it is a foundational building block for a modern private cloud. By eliminating siloed management and proprietary hardware lock-in, it allows IT teams to focus on delivering business value rather than managing and troubleshooting LUNs. Whether you are supporting AI, modern cloud-native apps, traditional apps, or virtual desktops, vSAN with VCF provides the scalability and resilience required for the next generation of enterprise workloads.