NetBackup for Hyper-V backup fails with "FTL - snapshot preparation failed, status 156" when the VM has one or more VHD Set (.vhds) files.

Problem

NetBackup for Hyper-V backup fails with "FTL - snapshot preparation failed, status 156" when the VM has one or more VHD Set (.vhds) files.

Error Message

An error has occurred attempting to create snapshot. The following message can be found in bpfis log (VERBOSE = 5).

06:22:21.295 [10044.2880] <2> onlfi_vfms_logf: INF - HVLOG : HV_freeze - Failed to perform pre-backup tasks. Error: HVERR : Failed to create vm snapshot. Error: Checkpoint operation for 'Guest1-2016' failed. (Virtual machine ID 42241DBC-8270-4E07-850C-462B164E4113) Production checkpoints cannot be created for 'Guest1-2016'. (Virtual machine ID 42241DBC-8270-4E07-850C-462B164E4113) Cannot take checkpoint for 'Guest1-2016' because one or more shareable VHDX are attached and this is not part of a checkpoint collection.  (Virtual machine ID 42241DBC-8270-4E07-850C-462B164E4113) [../hyperv.cpp:229]

Cause

NetBackup for Hyper-V does not support snapshot-based backup of the VM that has one or more VHD Set (.vhds) files.

Solution

Install a NetBackup client inside VM and perform a file-level backup using Ms-Windows Policy type.