Ahsay Go - VMware Limitations

September 16, 2026
VDDK Backup Mode Limitations

  • Guest VMs with RDM (Raw Device Mapping) disks, or iSCSI initiator are not supported. As VMware is not able to create a snapshot of raw, RDM disks or iSCSI disks.

    Although guest VM level backups are not possible, it is recommended to install Ahsay Go directly onto the guest VM to perform backups.

  • Guest VMs with raw disks are not supported. As VMware is not able to create a snapshot of raw disks.

    To perform a backup of the guest VM, it must either be powered off before the backup job or alternatively install Ahsay Go directly onto the guest VM to perform backups.

  • Backup of guest VM snapshots are not supported.
  • Backup of guest VM state (e.g. power on state / suspend state) is not supported.
  • If a guest VM has virtual hard disks larger than 2 TB, VMware snapshot operations can take much longer to finish, therefore backups may take longer.

  • Guest VMs setup with PCI vSphere DirectPath I/O devices are not supported. As VMware is not able to create a snapshot of these devices.

    The guest VMs must be powered off before a backup can be made.

  • All independent disks both persistent and non-persistent are not supported. As VMware does not support snapshots of independent disks when the guest VM is powered on.

    To perform a backup of the guest VM, it must either be powered off before the backup job or alternatively install Ahsay Go directly onto the guest VM to perform backups.

    Backup of suspended guest VMs with independent disks are also not supported.

  • Guest VMs configured with bus sharing are not supported. As VMware does not support snapshots of this type of configuration.

    Although guest VM level backups are not possible, it is recommended to install Ahsay Go directly onto the guest VM to perform backups.

Granular Restore Limitations
  • Network drives which have not been setup or mapped in Windows are not supported.
  • Temporary folder location is not supported with individual login credentials but can still be setup separately using existing Windows User Authentication login.
  • It also does not support Pre-Backup and Post-Backup Commands.
  • Not supported on "Restore Raw file" and "Restore to local computer" options.
  • Due to the removal of VDDK library from Granular Restore (OpenDirect), Granular Restore is now available ONLY on ESXi or vCenter VMware Backup Sets.
vSAN Backup and Restore Limitations
  • Backup and restore of guest VMs on a Stretched vSAN Cluster will be slower since it will be dependent on the internet connection between the Ahsay Go staging machine and the VMware vCenter server compared with a non-Stretched vSAN Cluster backup and restore which is using a LAN connection.

  • Run Direct restore may not be possible for Stretched vSAN Cluster since Ahsay Go is located on another site.

    The VMware vCenter server will have to power on and manage the VM, which is stored on a backup destination on the Ahsay Go staging machine through an internet connection.

Documentation