Enterprise infrastructure teams are at a pivotal moment. Private clouds have never been more important for organizations, as new workloads demand on-premises deployment. At the same time, VMware’s licensing and business model changes under Broadcom are forcing many organizations to evaluate alternatives for a private cloud foundation. The immediate need is clear: a reliable, enterprise-grade virtualization platform.
At Platform9, we’ve spent the last decade helping enterprises modernize their infrastructure. When we set out to build Private Cloud Director, our goal was to deliver a modern alternative to traditional virtualization platforms—starting with the features that are non-negotiable at scale: high availability, live migration, resource balancing, storage integration, software-defined networking, and enterprise security. We leveraged our extensive experience in the virtualization game, including our history leading the development of VMware’s foundational platform, to reimagine core virtualization capabilities needed by today’s IT organizations.
We designed Private Cloud Director not just as a better virtualization solution but as a next-generation private cloud platform—one that also supports modern applications, multi-tenant use cases, and long-term infrastructure flexibility.
We’re committed to four tenets for delivery: no-compromise virtualization, support for your choice of infrastructure, integration of modern cloud features, and seamless migration support.
In this post, we explore delivery of the first of these pillars: core virtualization capabilities. We will walk through the design principles that guided us, the foundational capabilities we built, and how those decisions help enterprises replace VMware today—while gaining a platform built to evolve with them.
Reliability for enterprise-scale virtualization
Enterprise infrastructure must be resilient by design. When thousands of virtual machines are running critical applications, uptime is non-negotiable—and performance must remain stable even as workloads shift and infrastructure evolves.
We built Private Cloud Director with core capabilities that work together to ensure continuous availability and efficient resource utilization at scale.
Dynamic Resource Rebalancing (DRR)
DRR is designed to keep workloads running smoothly even as demand fluctuates across hosts. It continuously monitors CPU and memory utilization and automatically migrates VMs in real time to prevent resource contention and performance degradation—without relying on static thresholds or manual intervention. DRR uses intelligent placement filters to ensure VMs are moved only to compatible hosts, maintaining policy compliance while reducing admin overhead. The result is a resilient, self-optimizing environment that adapts dynamically to changing workloads.
In our upcoming release, we will be introducing intelligent workload forecasting (beta feature) in DRR that uses a new predictive model. This enhancement leverages historical CPU and RAM usage data to:
- Forecast resource utilization trends
- Automatically select the most accurate prediction method
- Flag clusters for migration if predicted usage exceeds configured thresholds
Enabled by default at cluster creation, DRR innovations stand out in the market, delivering best-in-class resource utilization and stability in enterprise environments.
VM and storage live migration
VM live migration enables running VMs to move across hosts—or their storage to shift across back ends—without downtime. For VMs, this means moving memory and compute state seamlessly using a pre-copy approach, followed by a brief stop-and-copy phase that maintains service continuity.
Platform9 expands this capability by also supporting storage live migration:
- For VMs running on local (ephemeral) disk, the platform automatically replicates their data to the target host during migration.
- For VMs using block storage, volumes can move between storage back ends or change tier through live retyping—while the VM remains online
These combined capabilities match enterprise needs for operational flexibility: whether moving VMs for load balancing, maintenance, or infrastructure upgrades, both compute and storage can be remapped without interruption. That seamless migration—spanning both VM state and storage—ensures continuity and reflects a mature, best-in-class virtualization foundation.
Virtual machine high availability (VM HA)
VM HA continuously monitors host health within the cluster and automatically restarts VMs on healthy hosts when failures occur. Configurable per cluster, it requires shared storage and two or more hosts to ensure failover. This automated recovery minimizes downtime, protects production workloads from hardware or OS failures, and delivers best-in-class enterprise reliability without manual intervention.
These features are tightly integrated into the core platform—not layered on after the fact. That allows Private Cloud Director to maintain consistent performance and uptime, even under unpredictable load or hardware failure scenarios.
Designing for storage flexibility from the start
When we designed Private Cloud Director, we knew storage couldn’t be an afterthought. In enterprise environments, storage directly impacts performance, availability, and operations—and it often represents a significant portion of infrastructure spend. Many platforms today, especially hyperconverged ones, offer high performance and ease of use, but they also require adopting proprietary storage stacks. We took a different approach: to give enterprises the flexibility to use their existing storage investments without forcing a new hardware or software model.
- Seamless integration with existing storage systems: Private Cloud Director integrates with the storage systems enterprises already rely on—whether high-performance block storage or network-attached file storage.
- Support for multiple storage tiers: It also supports multiple storage tiers, allowing teams to align workloads with the right performance and cost profiles.
- Standards-based flexibility: This flexibility is made possible through open standards, avoiding the constraints of proprietary formats or vendor-specific protocols.
- Consistent policy management experience: Just as importantly, we designed the experience to be consistent. Storage policies are defined and managed through a unified interface, enabling teams to control allocation without custom automation or unfamiliar tools.
In short, Private Cloud Director provides an open, flexible, and enterprise-friendly storage foundation—so organizations can maximize their investments without compromising control or performance.
Building a programmable and secure network
We also treated networking as a foundational component of the platform—not an add-on. We recognized that for a private cloud to scale and remain secure, it needs a programmable, flexible networking model that supports workload isolation, access control, and operational simplicity.
- Built-in SDN and micro-segmentation: Private Cloud Director includes built-in support for software-defined networking (SDN) and micro-segmentation.
- Flexible, secure virtual networking: Virtual switches at the host or cluster level enable flexible topologies and enable other features such as DRR, HA, live migration etc, while features like port security (security groups), NIC teaming, and firewall rules provide fine-grained traffic control. These capabilities ensure secure communication between virtual machines while maintaining consistent policies across hosts.
- Essential networking services included: To minimize operational overhead, we also included essential networking services out of the box—DNS, load balancers, IP address management (IPAM), and virtual firewalls. These are delivered as part of the core platform, reducing the need for external tooling and accelerating deployment.
- Integration with existing enterprise networks: We knew many enterprises rely on existing networking and security appliances. That’s why Private Cloud Director integrates with systems like Fortinet and Cisco, allowing teams to extend their current architecture without compromise.
Networking is central to performance, security, and manageability in any private cloud. We designed it that way from the beginning—so teams can focus on building infrastructure, not stitching it together.
Operational security by design
Security isn’t something that can be added after the fact—it must be designed into the platform from day one. That principle guided every decision we made while building Private Cloud Director.
- Granular access control and audit logging: We started by enforcing strong access control across all layers of the system. Administrators can define granular roles and permissions, ensuring each team member has only the access they need. Built-in audit logging helps teams track changes and support incident response.
- Secure multi-tenancy by default: We also designed for secure multi-tenancy. In environments where teams or projects must remain isolated, Private Cloud Director enforces full network and resource separation by default—ensuring that each tenant operates securely and independently.
- Automated security operations: Security operations are automated where possible. Patching and upgrades are delivered through well-defined processes and automation. This helps avoid configuration drift and ensures consistency across large-scale deployments.
- Support for enterprise governance standards: Finally, we built the system to align with common enterprise governance practices. That includes support for external identity providers such as LDAP and SSO, granular role-based access control, and strict isolation policies. These features help organizations meet internal security and operational standards while maintaining flexibility in deployment.
Security in Private Cloud Director isn’t an add-on or an afterthought. It’s foundational—so that enterprises can operate with confidence at any scale.
Conclusion: Uncompromised delivery of virtualization capabilities, built for what’s next
When we started building Private Cloud Director, our goal wasn’t to replicate what already existed—it was to reimagine what a private cloud platform should look like for today’s enterprise. That meant delivering the critical enterprise virtualization capabilities teams depend on every day. But it also meant looking ahead. Enterprises need more than a replacement for yesterday’s stack—they need a platform that can evolve with them. Private Cloud Director is built to provide that path forward: a modern, open, and scalable system that supports both current VM-based workloads and the future of multi-tenant, cloud-native applications.
Whether you’re rethinking your virtualization strategy in light of licensing changes or preparing for a broader private cloud transformation, Private Cloud Director is designed to help you make that transition—on your terms, at your pace, and without compromise.
Contact the Platform9 team today to discuss how your organization can begin its journey to Private Cloud Director.
