Fresh CBT Client long incremental backup ? Why

Dear all,

Using URBackup since a long time, I decided to test the CBT module on one client station.

I bought and installed the latest stableCBT 2.4.12 on one workstation, a W10 machine with 60GB used on a 120GB SSD.

For this test, I launched first a full image backup: 3h13 length.

|Information|11/03/21 18:54|Starting unscheduled full image backup of volume “C:”…|
| — | — | — |
|Information|11/03/21 22:08|Transferred 87.4992 GB - Average speed: 64.8564 MBit/s|
|Information|11/03/21 22:08|Time taken for backing up client secretariat: 3h 13m 20s|
|Information|11/03/21 22:08|Backup succeeded|

Then this morning I launched an incremental image backup: It’s showing: 9,5GB - it took 20 mn!!!
|12/03/21 08:32 |INFO |Starting unscheduled incremental image backup of volume “C:”…|
|12/03/21 08:32 |DEBUG |Backing up SYSVOL…|
|12/03/21 08:33 |DEBUG |Backing up SYSVOL done.|
|12/03/21 08:33 |DEBUG |Backing up EFI System Partition…|
|12/03/21 08:33 |DEBUG |Backing up EFI System Partition done.|
|12/03/21 08:33 |INFO |Basing image backup on last full image backup|
|12/03/21 08:33 |INFO |Change block tracking active. Max 9.5791 GB have changed.|
|12/03/21 08:52 |INFO |Transferred 8.86501 GB - Average speed: 65.6973 MBit/s|
|12/03/21 08:52 |DEBUG |Script does not exist urbackup/post_incr_imagebackup|
|12/03/21 08:52 |INFO |Time taken for backing up client secretariat: 19m 33s|
|12/03/21 08:52 |INFO |Backup succeeded|

The station content was the SAME !!
why CBT is using so much element for backup??
As the station was not used / not restarted so NO NOW ELEMENTS on the workstation but CBT Urbackup found nevertheless 19GB to backup ???

Maybe I missed some configuration element (I only plug CBT on the workstation) or something like that, please advice!

you have probably defragmented the disk

@reine for sure not!! as I wrote the station was not touched/used anymore. disk is standard SSD.

no defrag at all! absolutely nothing!!
station was EXACTLY the same :slight_smile: (no reboot - I just wait some hours before lauching the image incremental backup)

so I don’t understand why 9GB incremental as the station was the same???

I’m able to make again the test or other tests if necessary. (try again a full backup then immediate CBT incremental).

CBT documentation lacks of information about CBT. :frowning: no info about potential server configuration (or station) but maybe it’s not necessary

I just installed CBT on this specific windows station, reboot and that’s all I launched URBACKUP.

Any clue???

PS: I need to buy & deploy CBT on 4 other machines but before I need to solve this problem! :slight_smile:

You do need to specify which volumes should use CBT on the server in the settings for that client.

It’s also worth right clicking the tray icon on the client, either " Infos" or “About” has a “Show CBT status” button, which will tell you if it’s actually in use.

All that said, Win 10 is quite capable of having multiple GB of change happen if left alone for hours, particularly if it decides to download setup for a feature update in the background.

@Bearded_Blunder I already specify the only disk which is C:
Show CBT status is showing it’s in use…

I’ve made a new test today:
a new FULL image backup on same workstation. 3h16 (even we’re on 10GB LAN :wink:

12/03/21 16:21 Starting unscheduled full image backup of volume “C:”…
12/03/21 19:38 Transferred 88.6932 GB - Average speed: 64.5757 MBit/s
12/03/21 19:38 Time taken for backing up client secretariat: 3h 16m 51s
12/03/21 19:38 Backup succeeded

THEN immediately I launched an INCREMENTAL IMAGE on this workstation (5 seconds after full image was done)

–>> INCREMENTAL is now 4.26GB length …

12/03/21 19:38 INFO Starting unscheduled incremental image backup of volume “C:”…
12/03/21 19:38 DEBUG Backing up SYSVOL…
12/03/21 19:38 DEBUG Backing up SYSVOL done.
12/03/21 19:38 DEBUG Backing up EFI System Partition…
12/03/21 19:38 DEBUG Backing up EFI System Partition done.
12/03/21 19:38 INFO Basing image backup on last full image backup
12/03/21 19:39 INFO Change block tracking active. Max 4.26123 GB have changed.
12/03/21 19:47 INFO Transferred 3.75634 GB - Average speed: 60.467 MBit/s
12/03/21 19:47 DEBUG Script does not exist urbackup/post_incr_imagebackup
12/03/21 19:47 INFO Time taken for backing up client secretariat: 8m 59s
12/03/21 19:47 INFO Backup succeeded

Windows had no time to upload/upgrade anything. And Incremental was even 4.6GB!!
That’s weird.

Any clue?

How CBT is working from your side??? Do you use it with image and not file backup?

How to solve this problem???

Do have any Browsers running?
Chrome, Firefox, and others continually write to the hard drive.
The Registry process also does a lot of writing to the hard drive.
Add I/O Writes to the Task Manager display, then click the I/O Writes at top of column to show sorted order.

CBT is for Image backup only.