===== [V7] ISSUE: Fail to load CBT, will perform normal in-file delta (Hyper-V VM backup) =====
Article ID:
5221
Reviewed:
2017-10-06
Product Version:
AhsayOBM: 7.9.0.0 - 7.13.x
OS: Windows
ATTENTION
1st January, 2022: v7 officially End-of-Life [details]
===== Problem Description =====
When performing a Hyper-V VM backup (Hyper-V 2008 R2 or newer releases) with a backup destination set to AhsayCBS, Cloud storage, or SFTP / FTP storage, the following warning message is displayed on the backup client interface, or in the backup report:
No.
|
Type
|
Timestamp
|
Log
|
*
|
...
|
...
|
...
|
*
|
info
|
...
|
Start creating Shadow Copy Set...
|
*
|
info
|
...
|
Shadow Copy Set successfully created
|
*
|
warn
|
YYYY/MM/DD
hh:mm:ss
|
Fail to load CBT, will perform normal in-file delta
|
*
|
...
|
...
|
...
|
===== Cause =====
The CBT (Change Block Tracking) feature is only supported for Hyper-V 2008 R2 or new releases, with backup destination set to a local or network drive relative to the Hyper-V host.
===== Resolution =====
To utilize the CBT (Change Block Tracking) feature for Hyper-V 2008 R2 or newer releases, re-configure the backup destination of the affected MS VM backup set to a local destination (local or network drive):
-
Login to the AhsayOBM user interface.
-
Select Backup Sets, then the corresponding MS Hyper-V backup set.
-
Click on Add, then select Local / Mapped Drive / Removable Drive under the Destination storage drop down menu:
-
Click Test to confirm if the destination is accessible, then OK and Save to confirm the changes.
Note: Delete the previous backup destination (e.g. AhsayCBS, Cloud storage, or SFTP / FTP storage) afterward, and re-create a separate backup set that does not utilize the Hyper-V CBT feature if necessary.
Refer to Chapter 1 in the
Ahsay Online Backup Manager - Microsoft Hyper-V Guest Virtual Machine Backup & Restore Guide
for details on MS Hyper-V backup set.
===== Keywords =====
vm, virtual, machine, hyper-v, hyperv, hyper, cbt, block, tracking, track, infile, delta