Virtualized Cluster
Private Cloud Director enables you to manage and operate multiple virtualized clusters from a single PCD region.
Use Cases
- Multi-Tenant Isolation - You can assign different tenants to separate clusters to enforce resource boundaries and fault domain separation. This prevents noisy neighbor issues and enhances security between tenant environments.
- Licensing Requirements - Some specialized software like Oracle database may require isolation of hosts with the software license enabled. Creating a separate cluster will allow you to do this.
- Hardware Specialization - You can group hosts with similar capabilities (such as GPU-enabled or high-memory machines) into dedicated clusters to optimize specialized workload performance and resource utilization.
Understanding a Virtualized Cluster
A virtualized cluster is a grouping of interconnected physical servers or hosts, with certain cluster level features operating at the group level. Resources such as CPU, Memory across all hosts in a virtualized cluster are presented as a single pool of resources such that when a new virtual machine gets created on the virtualized cluster, it may get placed on any of the underlying physical servers, based on capacity and other provisioning constraints.
All clusters within a region operate under a single cluster blueprint, ensuring consistency in base configurations while allowing for cluster-specific customization.
Each virtualized cluster provides two key features that enable you to run production workloads on the clusters.
Virtual Machine High Availability (VM HA)
VM HA provides automatic fault tolerance for your workloads. When enabled:
- The system continuously monitors host health across the cluster
- If a host failure is detected, affected VMs are automatically recovered on healthy hosts
- Downtime is minimized without requiring manual intervention
- Business continuity is maintained even during infrastructure issues
Read more here about Virtual Machine High Availability (VM HA).
Dynamic Resource Rebalancing (DRR)
DRR works as a continuous optimization engine that:
- Monitors allocated capacity and real-time utilization metrics (CPU, memory) across all hosts within the cluster.
- Analyzes resource distribution patterns to identify imbalances
- Intelligently migrates VMs across hosts in the cluster to optimize resource utilization.
- Prevents hotspots and resource contention before they impact performance
This proactive approach ensures that your clusters maintain optimal performance even as workload patterns change over time.
Read more here about Dynamic Resource Rebalancing (DRR).
Create a Virtualized Cluster
To create a new virtualized cluster:
- Navigate to Infrastructure → Clusters → Add Cluster
- Provide a name for the cluster.
- Choose desired settings for:
- VMHA (Virtual Machine High Availability)
- DRR (Dynamic Resource Rebalancing)