VMware CBT, Hyper-V RCT, or Nutanix CRT Is Not Supported

Product version: 9.1

Last modified: 30 September 2019


During a backup, replication or recovery job, one of the following messages is displayed.

VMware CBT / Hyper-V RCT / Nutanix CRT is not supported by the VM.

Backup / Replication / Recovery will be performed using proprietary change tracking method. The job may take longer to complete.

Backup / Replication / Nutanix CRT Recovery of the VM has failed.

VMware CBT / Hyper-V RCT / Nutanix CRT is not supported by this VM.


VMware CBT (Changed Block Tracking), Hyper-V RCT (Resilient Change Tracking), and Nutanix CRT (Changed Region Tracking) are technologies that are used to track changes on virtual machines. NAKIVO Backup & Replication uses these technologies to create incremental backups. When using these technologies is not possible, NAKIVO Backup & Replication uses NAKIVO’s proprietary change tracking method. The proprietary change tracking technology works slower than the other three technologies.

VMware CBT is supported on ESXi hosts v4.1 or later and VMs with virtual hardware version 7 or later.

Hyper-V RCT is supported on Hyper-V 2016/Hyper-V 2019 Server and virtual machine configuration version 8.

Nutanix CRT is supported on Nutanix AHV cluster environments version or later.


Consider upgrading hypervisor and virtual hardware (for VMware), virtual machine configuration (for Hyper-V), or AOS (for Nutanix AHV) .