Harvester: Intro and Setup    

Dienstag, 17 August, 2021
I mentioned about a month back that I was using Harvester in my home lab. I didn’t go into much detail, so this post will bring some more depth. We will cover what Harvester does, as well as my hardware, installation, setup and how to deploy your first virtual machine. Let’s get started.

What is Harvester?

Harvester is Rancher’s open source answer to a hyperconverged infrastructure platform. Like most things Rancher is involved with, it is built on Kubernetes using tools like KubeVirt and Longhorn. KubeVirt is an exciting project that leverages KVM and libvirt to run virtual machines inside Kubernetes; this allows you to run both containers and VMs in your cluster. It reduces operational overhead and provides consistency. This combination of tried and tested technologies provides an open source solution in this space.

It is also designed to be used with bare metal, making it an excellent option for a home lab.


If you check the hardware requirements, you will notice they focus more on business usage. So far, my personal experience says that you want at least a 4 core/8 thread CPU, 16GB of RAM, and a large SSD, preferably an NVMe drive. Anything less resource-wise doesn’t leave enough capacity for running many containers or VMs. I will install it on an Intel NUC 8i5BEK, which has an Intel Core i5-8259U. As far as RAM, it has 32GB of RAM and a 512GB NVMe drive. It can handle running Harvester without any issues. Of course, this is just my experience; your experience may differ.


Harvester ships as an ISO, which you can download on the GitHub Releases page. You can pull it quickly using wget.

$ wget https://releases.rancher.com/harvester/v0.2.0/harvester-amd64.iso

Once you have it downloaded, you will need to create a bootable USB. I typically use Balena Etcher since it is cross-platform and intuitive. Once you have a bootable USB, place it in the machine you want to use and boot the drive. This screen should greet you:

Select “New Cluster”:

Select the drive you want to use.

Enter your hostname, select your network interface, and make sure you use automatic DHCP.

You will then be prompted to enter your cluster token. This can be any phrase you want; I recommend using your password manager to generate one.

Set a password to use, and remember that the default user name is rancher.

The following several options are attractive, especially if you want to leverage your SSH keys used in GitHub. Since this is a home lab, I left the SSH keys, proxy and cloud-init setup blank. In an enterprise environment, this would be really useful. Now you will see the final screen before installation. Verify that everything is configured to your desires before proceeding.

If it all looks great, proceed with the installation. It will take a few minutes to complete; when it does, you will need to reboot.

After the reboot, the system will startup, and you will see a screen letting you know the URL for Harvester and the system’s status. Wait until it reports that Harvester is ready before trying to connect.

Great! It is now reporting that it is up and running, so it’s now time to set up Harvester.

Initial Setup

We can navigate to the URL listed once the OS boots. Mine is https://harvest:30443. It uses a self-signed certificate by default, so you will see a warning in your browser. Just click on „advanced“ to proceed, and accept it. Set a password for the default admin account.

Now you should see the dashboard and the health of the system.

I like to disable the default account and add my own account for authentication. Probably not necessary for a home lab, but a good habit to get into. First, you need to navigate to it.

Now log out and back in with your new account. Once that’s finished, we can create our first VM.

Deploying Your First VM

Harvester has native support for qcow2 images and can import those from a URL. Let’s grab the URL for openSUSE Leap 15.3 JeOS image.


The JeOS image for openSUSE is roughly 225MB, which is a perfect size for downloading and creating VMs quickly. Let’s make the image in Harvester.

Create a new image, and add the URL above as the image URL.

You should now see it listed.

Now we can create a VM using that image. Navigate to the VM screen.

Once we’ve made our way to the VM screen, we’ll create a new VM.

When that is complete, the VM will show up in the list. Wait until it has been started, then you can start using it.

Wrapping Up

In this article, I wanted to show you how to set up VMs with Harvester, even starting from scratch! There are plenty of features to explore and plenty more on the roadmap. This project is still early in its life, so now is a great time to jump in and get involved with its direction.

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Hyperconverged Infrastructure and Harvester

Montag, 2 August, 2021

Virtual machines (VMs) have transformed infrastructure deployment and management. VMs are so ubiquitous that I can’t think of a single instance where I deployed production code to a bare metal server in my many years as a professional software engineer.

VMs provide secure, isolated environments hosting your choice of operating system while sharing the resources of the underlying server. This allows resources to be allocated more efficiently, reducing the cost of over-provisioned hardware.

Given the power and flexibility provided by VMs, it is common to find many VMs deployed across many servers. However, managing VMs at this scale introduces challenges.

Managing VMs at Scale

Hypervisors provide comprehensive management of the VMs on a single server. The ability to create new VMs, start and stop them, clone them, and back them up are exposed through simple management consoles or command-line interfaces (CLIs).

But what happens when you need to manage two servers instead of one? Suddenly you find yourself having first to gain access to the appropriate server to interact with the hypervisor. You’ll also quickly find that you want to move VMs from one server to another, which means you’ll need to orchestrate a sequence of shutdown, backup, file copy, restore and boot operations.

Routine tasks performed on one server become just that little bit more difficult with two, and quickly become overwhelming with 10, 100 or 1,000 servers.

Clearly, administrators need a better way to manage VMs at scale.

Hyperconverged Infrastructure

This is where Hyperconverged Infrastructure (HCI) comes in. HCI is a marketing term rather than a strict definition. Still, it is typically used to describe a software layer that abstracts the compute, storage and network resources of multiple (often commodity or whitebox) servers to present a unified view of the underlying infrastructure. By building on top of the virtualization functionality included in all major operating systems, HCI allows many systems to be managed as a single, shared resource.

With HCI, administrators no longer need to think in terms of VMs running on individual servers. New hardware can be added and removed as needed. VMs can be provisioned wherever there is appropriate capacity, and operations that span servers, such as moving VMs, are as routine with 2 servers as they are with 100.


Harvester, created by Rancher, is open source HCI software built using Kubernetes.

While Kubernetes has become the defacto standard for container orchestration, it may seem like an odd choice as the foundation for managing VMs. However, when you think of Kubernetes as an extensible orchestration platform, this choice makes sense.

Kubernetes provides authentication, authorization, high availability, fault tolerance, CLIs, software development kits (SDKs), application programming interfaces (APIs), declarative state, node management, and flexible resource definitions. All of these features have been battle tested over the years with many large-scale clusters.

More importantly, Kubernetes orchestrates many kinds of resources beyond containers. Thanks to the use of custom resource definitions (CRDs), and custom operators, Kubernetes can describe and provision any kind of resource.

By building on Kubernetes, Harvester takes advantage of a well tested and actively developed platform. With the use of KubeVirt and Longhorn, Harvester extends Kubernetes to allow the management of bare metal servers and VMs.

Harvester is not the first time VM management has been built on top of Kubernetes; Rancher’s own RancherVM is one such example. But these solutions have not been as popular as hoped:

We believe the reason for this lack of popularity is that all efforts to date to manage VMs in container platforms require users to have substantial knowledge of container platforms. Despite Kubernetes becoming an industry standard, knowledge of it is not widespread among VM administrators.

To address this, Harvester does not expose the underlying Kubernetes platform to the end user. Instead, it presents more familiar concepts like VMs, NICs, ISO images and disk volumes. This allows Harvester to take advantage of Kubernetes while giving administrators a more traditional view of their infrastructure.

Managing VMs at Scale

The fusion of Kubernetes and VMs provides the ability to perform common tasks such as VM creation, backups, restores, migrations, SSH-Key injection and more across multiple servers from one centralized administration console.

Consolidating virtualized resources like CPU, memory, network, and storage allows for greater resource utilization and simplified administration, allowing Harvester to satisfy the core premise of HCI.


HCI abstracts the resources exposed by many individual servers to provide administrators with a unified and seamless management interface, providing a single point to perform common tasks like VM provisioning, moving, cloning, and backups.

Harvester is an HCI solution leveraging popular open source projects like Kubernetes, KubeVirt, and Longhorn, but with the explicit goal of not exposing Kubernetes to the end user.

The end result is an HCI solution built on the best open source platforms available while still providing administrators with a familiar view of their infrastructure.

Download Harvester from the project website and learn more from the project documentation.

Meet the Harvester developer team! Join our free Summer is Open session on Harvester: Tuesday, July 27 at 12pm PT and on demand. Get details about the project, watch a demo, ask questions and get a challenge to complete offline.

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Announcing Harvester Beta Availability

Freitag, 28 Mai, 2021

It has been five months since we announced project Harvester, open source hyperconverged infrastructure (HCI) software built using Kubernetes. Since then, we’ve received a lot of feedback from the early adopters. This feedback has encouraged us and helped in shaping Harvester’s roadmap. Today, I am excited to announce the Harvester v0.2.0 release, along with the Beta availability of the project!

Let’s take a look at what’s new in Harvester v0.2.0.

Raw Block Device Support

We’ve added the raw block device support in v0.2.0. Since it’s a change that’s mostly under the hood, the updates might not be immediately obvious to end users. Let me explain more in detail:

In Harvester v0.1.0, the image to VM flow worked like this:

  1. Users added a new VM image.

  2. Harvester downloaded the image into the built-in MinIO object store.

  3. Users created a new VM using the image.

  4. Harvester created a new volume, and copied the image from the MinIO object store.

  5. The image was presented to the VM as a block device, but it was stored as a file in the volume created by Harvester.

This approach had a few issues:

  1. Read/write operations to the VM volume needed to be translated into reading/writing the image file, which performed worse compared to reading/writing the raw block device, due to the overhead of the filesystem layer.

  2. If one VM image is used multiple times by different VMs, it was replicated many times in the cluster. This is because each VM had its own copy of the volume, even though the majority of the content was likely the same since they’re coming from the same image.

  3. The dependency on MinIO to store the images resulted in Harvester keeping MinIO highly available and expandable. Those requirements caused an extra burden on the Harvester management plane.

In v0.2.0, we’ve took another approach to tackle the problem, which resulted in a simpler solution that had better performance and less duplicated data:

  1. Instead of an image file on the filesystem, now we’re providing the VM with raw block devices, which allows for better performance for the VM.

  2. We’ve taken advantage of a new feature called Backing Image in the Longhorn v1.1.1, to reduce the unnecessary copies of the VM image. Now the VM image will be served as a read-only layer for all the VMs using it. Longhorn is now responsible for creating another copy-on-write (COW) layer on top of the image for the VMs to use.

  3. Since now Longhorn starts to manage the VM image using the Backing Image feature, the dependency of MinIO can be removed.

Image 02
A comprehensive view of images in Harvester

From the user experience perspective, you may have noticed that importing an image is instantaneous. And starting a VM based on a new image takes a bit longer due to the image downloading process in Longhorn. Later on, any other VMs using the same image will take significantly less time to boot up, compared to the previous v0.1.0 release and the disk IO performance will be better as well.

VM Live Migration Support

In preparation for the future upgrade process, VM live migration is now supported in Harvester v0.2.0.

VM live migration allows a VM to migrate from one node to another, without any downtime. It’s mostly used when you want to perform maintenance work on one of the nodes or want to balance the workload across the nodes.

One thing worth noting is, due to potential IP change of the VM after migration when using the default management network, we highly recommend using the VLAN network instead of the default management network. Otherwise, you might not be able to keep the same IP for the VM after migration to another node.

You can read more about live migration support here.

VM Backup Support

We’ve added VM backup support to Harvester v0.2.0.

The backup support provides a way for you to backup your VM images outside of the cluster.

To use the backup/restore feature, you need an S3 compatible endpoint or NFS server and the destination of the backup will be referred to as the backup target.

You can get more details on how to set up the backup target in Harvester here.

Image 03
Easily manage and operate your virtual machines in Harvester

In the meantime, we’re also working on the snapshot feature for the VMs. In contrast to the backup feature, the snapshot feature will store the image state inside the cluster, providing VMs the ability to revert back to a previous snapshot. Unlike the backup feature, no data will be copied outside the cluster for a snapshot. So it will be a quick way to try something experimental, but not ideal for the purpose of keeping the data safe if the cluster went down.

PXE Boot Installation Support

PXE boot installation is widely used in the data center to automatically populate bare-metal nodes with desired operating systems. We’ve also added the PXE boot installation in Harvester v0.2.0 to help users that have a large number of servers and want a fully automated installation process.

You can find more information regarding how to do the PXE boot installation in Harvester v0.2.0 here.

We’ve also provided a few examples of doing iPXE on public bare-metal cloud providers, including Equinix Metal. More information is available here.

Rancher Integration

Last but not least, Harvester v0.2.0 now ships with a built-in Rancher server for Kubernetes management.

This was one of the most requested features since we announced Harvester v0.1.0, and we’re very excited to deliver the first version of the Rancher integration in the v0.2.0 release.

For v0.2.0, you can use the built-in Rancher server to create Kubernetes clusters on top of your Harvester bare-metal clusters.

To start using the built-in Rancher in Harvester v0.2.0, go to Settings, then set the rancher-enabled option to true. Now you should be able to see a Rancher button on the top right corner of the UI. Clicking the button takes you to the Rancher UI.

Harvester and Rancher share the authentication process, so once you’re logged in to Harvester, you don’t need to redo the login process in Rancher and vice versa.

If you want to create a new Kubernetes cluster using Rancher, you can follow the steps here. A reminder that VLAN networking needs to be enabled for creating Kubernetes clusters on top of the Harvester, since the default management network cannot guarantee a stable IP for the VMs, especially after reboot or migration.

What’s Next?

Now with v0.2.0 behind us, we’re working on the v0.3.0 release, which will be the last feature release before Harvester reaches GA.

We’re working on many things for v0.3.0 release. Here are some highlights:

  • Built-in load balancer
  • Rancher 2.6 integration
  • Replace K3OS with a small footprint OS designed for the container workload
  • Multi-tenant support
  • Multi-disk support
  • VM snapshot support
  • Terraform provider
  • Guest Kubernetes cluster CSI driver
  • Enhanced monitoring

You can get started today and give Harvester v0.2.0 a try via our website.

Let us know what you think via the Rancher User Slack #harvester channel. And start contributing by filing issues and feature requests via our github page.

Enjoy Harvester!

Announcing Harvester: Open Source Hyperconverged Infrastructure (HCI) Software

Mittwoch, 16 Dezember, 2020

Today, I am excited to announce project Harvester, open source hyperconverged infrastructure (HCI) software built using Kubernetes. Harvester provides fully integrated virtualization and storage capabilities on bare-metal servers. No Kubernetes knowledge is required to use Harvester.

Why Harvester?

In the past few years, we’ve seen many attempts to bring VM management into container platforms, including our own RancherVM, and other solutions like KubeVirt and Virtlet. We’ve seen some demand for solutions like this, mostly for running legacy software side by side with containers. But in the end, none of these solutions have come close to the popularity of industry-standard virtualization products like vSphere and Nutanix.

We believe the reason for this lack of popularity is that all efforts to date to manage VMs in container platforms require users to have substantial knowledge of container platforms. Despite Kubernetes becoming an industry standard, knowledge of it is not widespread among VM administrators. They are familiar with concepts like ISO images, disk volumes, NICs and VLANS – not concepts like pods and PVCs.

Enter Harvester.

Project Harvester is an open source alternative to traditional proprietary hyperconverged infrastructure software. Harvester is built on top of cutting-edge open source technologies including Kubernetes, KubeVirt and Longhorn. We’ve designed Harvester to be easy to understand, install and operate. Users don’t need to understand anything about Kubernetes to use Harvester and enjoy all the benefits of Kubernetes.

Harvester v0.1.0

Harvester v0.1.0 has the following features:

Installation from ISO

You can download ISO from the release page on Github and install it directly on bare-metal nodes. During the installation, you can choose to create a new cluster or add the current node into an existing cluster. Harvester will automatically create a cluster based on the information you provided.

Install as a Helm Chart on an Existing Kubernetes Cluster

For development purposes, you can install Harvester on an existing Kubernetes cluster. The nodes must be able to support KVM through either hardware virtualization (Intel VT-x or AMD-V) or nested virtualization.

VM Lifecycle Management

Powered by KubeVirt, Harvester supports creating/deleting/updating operations for VMs, as well as SSH key injection and cloud-init.

Harvester also provides a graphical console and a serial port console for users to access the VM in the UI.

Storage Management

Harvester has a built-in highly available block storage system powered by Longhorn. It will use the storage space on the node, to provide highly available storage to the VMs inside the cluster.

Networking Management

Harvester provides several different options for networking.

By default, each VM inside Harvester will have a management NIC, powered by Kubernetes overlay networking.

Users can also add additional NICs to the VMs. Currently, VLAN is supported.

The multi-network functionality in Harvester is powered by Multus.

Image Management

Harvester has a built-in image repository, allowing users to easily download/manage new images for the VMs inside the cluster.

The image repository is powered by MinIO.

Image 01


To install Harvester, just load the Harvester ISO into your bare-metal machine and boot it up.

Image 02

For the first node where you install Harvester, select Create a new Harvester cluster.

Later, you will be prompted to enter the password that will be used to enter the console on the host, as well as “Cluster Token.” The Cluster Token is a token that’s needed later by other nodes that want to join the same cluster.

Image 03

Then you will be prompted to choose the NIC that Harvester will use. The selected NIC will be used as the network for the management and storage traffic.

Image 04

Once everything has been configured, you will be prompted to confirm the installation of Harvester.

Image 05

Once installed, the host will be rebooted and boot into the Harvester console.

Image 06

Later, when you are adding a node to the cluster, you will be prompted to enter the management address (which is shown above) as well as the cluster token you’ve set when creating the cluster.

See here for a demo of the installation process.

Alternatively, you can install Harvester as a Helm chart on your existing Kubernetes cluster, if the nodes in your cluster have hardware virtualization support. See here for more details. And here is a demo using Digital Ocean which supports nested virtualization.


Once installed, you can use the management URL shown in the Harvester console to access the Harvester UI.

The default user name/password is documented here.

Image 07

Once logged in, you will see the dashboard.

Image 08

The first step to create a virtual machine is to import an image into Harvester.

Select the Images page and click the Create button, fill in the URL field and the image name will be automatically filled for you.

Image 09

Then click Create to confirm.

You will see the real-time progress of creating the image on the Images page.

Image 10

Once the image is finished creating, you can then start creating the VM using the image.

Select the Virtual Machine page, and click Create.

Image 11

Fill in the parameters needed for creation, including volumes, networks, cloud-init, etc. Then click Create.

VM will be created soon.

Image 12

Once created, click the Console button to get access to the console of the VM.

Image 13

See here for a UI demo.

Current Status and Roadmap

Harvester is in the early stages. We’ve just released the v0.1.0 (alpha) release. Feel free to give it a try and let us know what you think.

We have the following items in our roadmap:

  1. Live migration support
  2. PXE support
  3. VM backup/restore
  4. Zero downtime upgrade

If you need any help with Harvester, please join us at either our Rancher forums or Slack, where our team hangs out.

If you have any feedback or questions, feel free to file an issue on our GitHub page.

Thank you and enjoy Harvester!

Rancher Wrap: Another Year of Innovation and Growth

Montag, 12 Dezember, 2022

2022 was another year of innovation and growth for SUSE’s Enterprise Container Management business. We introduced significant upgrades to our Rancher and NeuVector products, launched new open source projects and matured others. Exiting 2022, Rancher remains the industry’s most widely adopted container management platform and SUSE remains the preferred vendor for enabling enterprise cloud native transformation. Here’s a quick look at a few key themes from 2022.  

Security Takes Center Stage 

As the container management market matured in 2022, container security took center stage.  Customers and the open source community alike voiced concerns around the risks posed by their increasing reliance on hybrid-cloud, multi-cloud, and edge infrastructure. Beginning with the open sourcing of NeuVector, which we acquired in Q4 2021, in 2022 we continued to meet our customers’ most stringent security and assurance requirements, making strategic investments across our portfolio, including:  

  • Kubewarden – In June, we donated Kubewarden to the CNCF. Now a CNCF sandbox project, Kubewarden is an open source policy engine for Kubernetes that automates the management and governance of policies across Kubernetes clusters thereby reducing risk.  It also simplifies the management of policies by enabling users to integrate policy management into their CI/CD engines and existing infrastructure.  
  • SUSE NeuVector 5.1 – In November, we released SUSE Neuvector 5.1, further strengthening our already industry leading container security platform. 
  • Rancher Prime– Most recently, we introduced Rancher Prime, our new commercial offering, replacing SUSE Rancher.  Supporting our focus on security assurances, Rancher Prime offers customers the option of accessing their Rancher Prime software directly from a trusted private registry. Additionally, Rancher Prime FIPS-140-3 and SLSA Level 2 and 3 certifications will be finalized in 2023.

Open Source Continues to Fuel Innovation 

 Our innovation did not stop at security. In 2022, we also introduced new projects and matured others, including:  

  • Elemental – Fit for Edge deployments, Elemental is an open source project, that enables centralized management and operations of RKE2 and K3s clusters when deployed with Rancher. 
  • Harvester SUSE’s open-source cloud-native hyper-converged infrastructure (HCI) alternative to proprietary HCI is now utilized across more than 710+ active clusters. 
  • Longhorn – now a CNCF incubator project, Longhorn is deployed across more than 72,000 nodes. 
  • K3s – SUSE’s lightweight Kubernetes distribution designed for the edge which we donated to the CNCF, has surpassed 4 million downloads. 
  • Rancher Desktop – SUSE’s desktop-based container development environment for Windows, macOS, and Linux environments has surpassed 520,000 downloads and 4,000 GitHub stars since its January release. 
  • Epinio – SUSE’s Kubernetes-powered application development platform-as-a-service (PaaS) solution in which users you can deploy apps without setting up infrastructure yourself has surpassed 4,000 downloads and 300 stars on GitHub since its introduction in September. 
  • Opni – SUSE’s multi-cluster observability tool (including logging, monitoring and alerting) with AIOps has seen steady growth with over 75+ active deployments this year.  

 As we head into 2023, Gartner research indicates the container management market will grow ~25% CAGR to $1.4B in 2025. In that same time-period, 85% of large enterprises will have adopted container management solutions, up from 30% in 2022.  SUSE’s 30-year heritage in delivering enterprise infrastructure solutions combined with our market leading container management solutions uniquely position SUSE as the vendor of choice for helping organizations on their cloud native transformation journeys.  I can’t wait to see what 2023 holds in store! 

Understanding Hyperconverged Infrastructure at the Edge from Adoption to Acceleration

Donnerstag, 29 September, 2022

You may be tired of the regular three-tiered infrastructure and the management issues it can bring in distributed systems and maintenance. Or perhaps you’ve looked at your infrastructure and realized that you need to move away from its current configuration. If that’s the case, hyperconverged infrastructure (HCI) may be a good solution because it removes a lot of management overhead, acting like a hypervisor that can handle networking and storage.

There are some key principles behind HCI that bring to light the advantages it has. Particularly, it can help simplify the deployment of new nodes and new applications. Because everything inside your infrastructure runs on normal x86 servers, adding nodes is as simple as spinning up a server and joining it to your HCI cluster. From here, applications can easily move around on the nodes as needed to optimize performance.

Once you’ve gotten your nodes deployed and added to your cluster, everything inside an HCI can be managed by policies, making it possible for you to strictly define the behavior of your infrastructure. This is one of the key benefits of HCI — it uses a single management interface. You don’t need to configure your networking in one place, your storage in another, and your compute in a third place; everything can be managed cohesively.

This cohesive management is possible because an HCI relies heavily on virtualization, making it feasible to converge the typical three tiers (compute, networking and storage) into a single plane, offering you flexibility.

While HCI might be an overkill for simple projects, it’s becoming a best practice for various enterprise use cases. In this article, you’ll see some of the main use cases for wanting to implement HCI in your organization. We’ll also introduce Harvester as a modern way to get started easier.

While reading through these use cases, remember that the use of HCI is not limited to them. To benefit most from this article, think about what principles of HCI make the use cases possible, and perhaps, you’ll be able to come up with additional use cases for yourself.

Why you need a hyperconverged infrastructure

There are many use cases when it comes to HCI, and most of them are based on the fact that HCI is highly scalable and, more importantly, it’s easy to scale HCI. The concept started getting momentum back in 2009, but it wasn’t until 2014 that it started gaining traction in the community at large. HCI is a proven and mature technology that, in its essence, has worked the same way for many years.

The past few decades have seen virtualization become the preferred method for users to optimize their resource usage and manage their infrastructure costs. However, introducing new technology, such as containers, has required operators to shift their existing virtualized-focused infrastructure to integrate with these modern cloud-based solutions, bringing new challenges for IT operators to tackle.

Managing virtualized resources (and specifically VMs) can be quite challenging. This is where HCI can help. By automating and simplifying the management of virtual resources, HCI makes it easy for developers and team leads to leverage virtualization to the fullest and reduce the time to market their product, a crucial factor in determining the success of a project.

Following are some of the most popular ways to use HCI currently:

Edge computing

Edge computing is the principle of running workloads outside the primary data centers of a company. While there’s no single reason for wanting to use edge computing, the most popular reason is to decrease customer latency.

In edge computing, you don’t always need an extensive fleet of servers, and the amount of power you need will likely change based on the location. You’ll need more servers to serve New York City with a population of 8.3 million than you’d need to fill the entire country of Denmark with a population of 5.8 million. One of the most significant benefits of HCI is that it scales incredibly well and low. You’d typically want multiple nodes for reasons like backup, redundancy and high availability. But theoretically, it’s possible to scale down to a single node.

Given that HCI runs on normal hardware, it’s also possible for you to optimize your nodes for the workload you need. If your edge computing use case is to provide a cache for users, then you’d likely need more storage. However, if you’re implementing edge workers that need to execute small scripts, you’re more likely to need processing power and memory. With HCI, you can adapt the implementation to your needs.

Migrating to a Hybrid Cloud Model

Over the past decade, the cloud has gotten more and more popular. Many companies move to the cloud and later realize their applications are better suited to run on-premises. You will also find companies that no longer want to run things in their data centers and instead want to move them to the cloud. In both these cases, HCI can be helpful.

If you want to leverage the cloud, HCI can provide a similar user experience on-premise. HCI is sometimes described as a “cloud in a box” because it can offer similar services one would expect in a public cloud. Examples of this include a consistent API for allocating compute resources dynamically, load balancers and storage services. Having a similar platform is a good foundation for being able to move applications between the public cloud and on-premise. You can even take advantage of tools like Rancher that can manage cloud infrastructure and on-prem HCI from a single pane of glass.

Modernization strategy

Many organizations view HCI as an enabler in their modernization processes. However, modernization is quite different from migration.

Modernization focuses on redesigning existing systems and architecture to make the most efficient use of the new environment and its offerings. With its particular focus on simplifying the complex management of data, orchestration and workflows, HCI is perfect for modernization.

HCI enables you to consolidate your complex server architecture with all its storage, compute and network resources into smaller, easy-to-manage nodes. You can easily transform a node from a storage-first resource to a compute-first resource, allowing you to design your infrastructure how you want it while retaining simplicity.

Modern HCI solutions like Harvester can help you to run your virtualized and containerized workloads side by side, simplifying the operational and management components of infrastructure management while also providing the capabilities to manage workloads across distributed environments. Regarding automation, Harvester provides a unique approach by using cloud native APIs. This allows the user to automate using the same tools they would use to manage cloud native applications. Not switching between two “toolboxes” can increase product development velocity and decrease the overhead of managing complex systems. That means users of this approach get their product to market sooner and with less cost.

Virtual Desktop Infrastructure (VDI)

Many organizations maintain fleets of virtual desktops that enable their employees to work remotely while maintaining standards of security and performance. Virtual desktops are desktop environments that are not limited to the hardware they’re hosted in; they can be accessed remotely via the use of software. Organizations prefer them over hardware since they’re easy to provision, scale, and destroy on demand.

Since compute and storage are two strongly connected and important resources in virtual desktops, HCI can easily manage virtual desktops. HCI’s enhanced reliability provides VDI with increased fault tolerance and efficient capacity consumption. HCI also helps cut down costs for VDI as there is no need for separate storage arrays, dedicated storage networks, and related hardware.

Remote office/Branch office

A remote office/branch office (ROBO) is one of the best reasons for using HCI. In case you’re not familiar, it’s typical for big enterprises to have a headquarters where they host their data and internal applications. Then the ROBOs will either have a direct connection to the headquarters to access the data and applications or have a replica in their own location. In both cases, you will introduce more management and maintenance and other factors, such as latency.

With HCI, you can spin up a few servers in the ROBOs and add them to an HCI cluster. Now, you’re managing all your infrastructure, even the infrastructure in remote locations, through a single interface. Not only can this result in a better experience for the employees, but depending on how much customer interaction they have, it can result in a better customer experience.

In addition, with HCI, you’re likely to lower your total cost of ownership. While you would typically have to put up an entire rack of hardware in a ROBO, you’re now expected to accomplish the same with just a few servers.


After reading this article, you now know more about how HCI can be used to support a variety of use cases, and hopefully, you’ve come up with a few use cases yourself. This is just the beginning of how HCI can be used. Over the next decade or two, HCI will continue to play an important role in any infrastructure strategy, as it can be used in both on-premises data centers and the public cloud. The fact that it uses commodity x86 systems to run makes it suitable for many different use cases.

If you’re ready to start using HCI for yourself, take a look at Harvester. Harvester is a solution developed by SUSE, built for bare metal servers. It uses enterprise-grade technologies, such as KubernetesKubeVirt and Longhorn.

What’s Next:

Want to learn more about how Harvester and Rancher are helping enterprises modernize their stack speed? Sign up here to join our Global Online Meetup: Harvester on October 26th, 2022, at 11 AM EST.

A Path to Legacy Application Modernization Through Kubernetes

Mittwoch, 6 Juli, 2022

These legacy applications may have multiple services bundled into the same deployment unit without a logical grouping. They’re challenging to maintain since changes to one part of the application require changing other tightly coupled parts, making it harder to add or modify features. Scaling such applications is also tricky because to do so requires adding more hardware instances connected to load balancers. This takes a lot of manual effort and is prone to errors.

Modernizing a legacy application requires you to visualize the architecture from a brand-new perspective, redesigning it to support horizontal scaling, high availability and code maintainability. This article explains how to modernize legacy applications using Kubernetes as the foundation and suggests three tools to make the process easier.

Using Kubernetes to modernize legacy applications

A legacy application can only meet a modern-day application’s scalability and availability requirements if it’s redesigned as a collection of lightweight, independent services.

Another critical part of modern application architecture is the infrastructure. Adding more server resources to scale individual services can lead to a large overhead that you can’t automate, which is where containers can help. Containers are self-contained, lightweight packages that include everything needed for a service to run. Combine this with a cluster of hardware instances, and you have an infrastructure platform where you can deploy and scale the application runtime environment independently.

Kubernetes can create a scalable and highly available infrastructure platform using container clusters. Moving legacy applications from physical or virtual machines to Kubernetes-hosted containers offers many advantages, including the flexibility to use on-premises and multi-cloud environments, automated container scheduling and load balancing, self-healing capability, and easy scalability.

Organizations generally adopt one of two approaches to deploy legacy applications on Kubernetes: using virtual machines and redesigning the application.

Using virtual machines

A monolith application’s code and dependencies are embedded in a virtual machine (VM) so that images of the VM can run on Kubernetes. Frameworks like Rancher provide a one-click solution to run applications this way. The disadvantage is that the monolith remains unchanged, which doesn’t achieve the fundamental principle of using lightweight container images. It is also possible to run part of the application in VMs and containerize the less complex ones. This hybrid approach helps to break down the monolith to a smaller extent without huge effort in refactoring the application. Tools like Harvester can help while managing the integration in this hybrid approach.

Redesigning the application

Redesigning a monolithic application to support container-based deployment is a challenging task that involves separating the application’s modules and recreating them as stateless and stateful services. Containers, by nature, are stateless and require additional mechanisms to handle the storage of state information. It’s common to use the distributed storage of the container orchestration cluster or third-party services for such persistence.

Organizations are more likely to adopt the first approach when the legacy application needs to move to a Kubernetes-based solution as soon as possible. This way, they can have a Kubernetes-based solution running quickly with less business impact and then slowly move to a completely redesigned application. Although Kubernetes migration has its challenges, some tools can simplify this process. The following are three such solutions.


Rancher provides a complete container management platform for Kubernetes, giving you the tools to successfully run Kubernetes anywhere. It’s designed to simplify the operational challenges of running multiple Kubernetes clusters across different infrastructure environments. Rancher provides developers with a complete Kubernetes environment, irrespective of the backend, including centralized authentication, access control and observability features:

  • Unified UI: Most organizations have multiple Kubernetes clusters. DevOps engineers can sometimes face challenges when manually provisioning, managing, monitoring and securing thousands of cluster nodes while establishing compliance. Rancher lets engineers manage all these clusters from a single dashboard.
  • Multi-environment deployment: Rancher helps you create Kubernetes clusters across multiple infrastructure environments like on-premises data centers, public clouds and edge locations without needing to know the nuances of each environment.
  • App catalog: The Rancher app catalog offers different application templates. You can easily roll out complex application stacks on top of Kubernetes with the click of a button. One example is Longhorn, a distributed storage mechanism to help store state information.
  • Security policies and role-based access control: Rancher provides a centralized authentication mechanism and role-based access control (RBAC) for all managed clusters. You can also create pod-level security policies.
  • Monitoring and alerts: Rancher offers cluster monitoring facilities and the ability to generate alerts based on specific conditions. It can help transport Kubernetes logs to external aggregators.


Harvester is an open source, hyperconverged infrastructure solution. It combines KubeVirt, a virtual machine add-on, and Longhorn, a cloud native, distributed block storage add-on along with many other cloud native open source frameworks. Additionally, Harvester is built on Kubernetes itself.

Harvester offers the following benefits to your Kubernetes cluster:

  • Support for VM workloads: Harvester enables you to run VM workloads on Kubernetes. Running monolithic applications this way helps you quickly migrate your legacy applications without the need for complex cluster configurations.
  • Cost-effective storage: Harvester uses directly connected storage drives instead of external SANs or cloud-based block storage. This helps significantly reduce costs.
  • Monitoring features: Harvester comes with Prometheus, an open source monitoring solution supporting time series data. Additionally, Grafana, an interactive visualization platform, is a built-in integration of Harvester. This means that users can see VM or Kubernetes cluster metrics from the Harvester UI.
  • Rancher integration: Harvester comes integrated with Rancher by default, so you can manage multiple Harvester clusters from the Rancher management UI. It also integrates with Rancher’s centralized authentication and RBAC.


Longhorn is a distributed cloud storage solution for Kubernetes. It’s an open source, cloud native project originally developed by Rancher Labs, and it integrates with the Kubernetes persistent volume API. It helps organizations use a low-cost persistent storage mechanism for saving container state information without relying on cloud-based object storage or expensive storage arrays. Since it’s deployed on Kubernetes, Longhorn can be used with any storage infrastructure.

Longhorn offers the following advantages:

  • High availability: Longhorn’s microservice-based architecture and lightweight nature make it a highly available service. Its storage engine only needs to manage a single volume, dramatically simplifying the design of storage controllers. If there’s a crash, only the volume served by that engine is affected. The Longhorn engine is lightweight enough to support as many as 10,000 instances.
  • Incremental snapshots and backups: Longhorn’s UI allows engineers to create scheduled jobs for automatic snapshots and backups. It’s possible to execute these jobs even when a volume is detached. There’s also an adequate provision to prevent existing data from being overwritten by new data.
  • Ease of use: Longhorn comes with an intuitive dashboard that provides information about volume status, available storage and node status. The UI also helps configure nodes, set up backups and change operational settings.
  • Ease of deployment: Setting up and deploying Longhorn just requires a single click from the Rancher marketplace. It’s a simple process, even from the command-line interface, because it involves running only certain commands. Longhorn’s implementation is based on the container storage interface (CSI) as a CSI plug-in.
  • Disaster recovery: Longhorn supports creating disaster recovery (DR) volumes in separate Kubernetes clusters. When the primary cluster fails, it can fail over to the DR volume. Engineers can configure recovery time and point objectives when setting up that volume.
  • Security: Longhorn supports data encryption at rest and in motion. It uses Kubernetes secret storage for storing the encryption keys. By default, backups of encrypted volumes are also encrypted.
  • Cost-effectiveness: Being open source and easily maintainable, Longhorn provides a cost-effective alternative to the cloud or other proprietary services.


Modernizing legacy applications often involves converting them to containerized microservice-based architecture. Kubernetes provides an excellent solution for such scenarios, with its highly scalable and available container clusters.

The journey to Kubernetes-hosted, microservice-based architecture has its challenges. As you saw in this article, solutions are available to make this journey simpler.

SUSE is a pioneer in value-added tools for the Kubernetes ecosystem. SUSE Rancher is a powerful Kubernetes cluster management solution. Longhorn provides a storage add-on for Kubernetes and Harvester is the next generation of open source hyperconverged infrastructure solutions designed for modern cloud native environments.