Software that runs inside the Nutanix Controller VM on the hypervisor and delivers the platform's functions. Joining a cluster requires a node to pair it with a hypervisor in a supported combination.
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Terms in this definition
- Agents (classic) API
First-generation Foundry Agent Service API, based on threads, messages and runs. It is deprecated, replaced by conversations and responses, and retires on 31 March 2027.
- CVM
A VM required on the hypervisor of every node in a Nutanix cluster, with AOS as its operating system. Every one needs a static IP address of its own.
- Hypervisor
The virtualisation software allowing many isolated virtual machines to run on a single physical server. The cloud provider looks after it whichever service type is used.
Related terms
- AES
A symmetric block cipher. Software-only encryption of stored data in AOS uses the 256-bit form, while SSH with keys can use the CTR modes at 128, 192 or 256 bits.
- Cluster Maintenance Utilities
Software on the cluster that LCM keeps up to date; the suggested sequence places it after AOS but ahead of AHV.
- Cluster rebuild preference
Decides how rebuilds behave during planned maintenance. Smart is the default from AOS 6.8 and separates maintenance from real failures so fewer rebuilds run needlessly; the other option is Immediate, and the deprecated Delayed becomes Smart.
- Cluster unregistration
Detaching a cluster from Prism Central, a step Nutanix advises against. With AOS 7.3 onwards it may join another instance, though not its original one or any instance paired with that.
- Default storage policy
Sets compression and replication factor, leaving everything else to the cluster's storage settings, and offers no encryption. Prism Central has generated it since pc.2024.1, with full support on AOS 6.8 onwards.
- Distributed Storage Fabric
AOS provides storage through this layer: AHV VMs get snapshots, clones, data protection and provisioning straight from it, and see their disks as raw SCSI block devices.
- Foundation
Nutanix's own tool for building clusters, loading nodes first with AOS and a hypervisor that are supported together. Its three forms are the standalone VM, the app and the version in the CVM.
- LUKS
Encrypts stored configuration data for AHV and AOS, turned on during Foundation where AHV nodes have a TPM. Workload data is still covered by the separate AOS encryption, which remains in place alongside it.