Is CBT lost when creating new backup jobs?

[HouseAtreides]

Hi

I have Veeam Windows Agent installed on a Windows 2012 server and the CBT driver.

I have 4 agent backup jobs, each backs up 1 of 4 server drives. I can see each subsequent job uses CBT for incremental backups.

Am I correct to say that I cannot create a new agent backup job containing all 4 drives and maintain CBT data? i.e. the job will start with a Full backup the first time it is run because the CBT data is not available to it?

Thanks
HA

[HouseAtreides]

To be clearer ...

The Windows 2012 server has 4 disks

Agent Backup Job 1 - backs up disk1
Agent Backup Job 2 - backs up disk2
Agent Backup Job 3 - backs up disk3
Agent Backup Job 4 - backs up disk4

I want to create one job to backup all the disks:

Agent Backup Job - backs up disks 1, 2, 3, 4

If I do this, will the new job be able to start as an incremental using the CBT data that already exists in Agent Jobs 1, 2, 3 and 4? My assumption is no, it will start with a Full backup and only afters jobs will be incremental

[HouseAtreides]

Or maybe it is possible. According to the Veeam knowledgebase, CBTA data is stored in VCT files that are stored on the disk. So could a different backup job read this data (stored inside the VM) and use the CBT data?

"Information about changed data blocks is registered in special VCT files. VCT files are stored in the C:\ProgramData\Veeam\EndpointData\CtStore folder on the Veeam Agent computer. When the backup job runs, Veeam Agent for Microsoft Windows uses VCT files to find out what data blocks have changed since the last run of the job, and copies only changed data blocks from the backed-up volume."

https://helpcenter.veeam.com/docs/agent ... tml?ver=30