When using Rsync as a post job activity to copy backup files to an offsite location one of the problems that is encountered is that after the second backup is using reverse incremental, Rsync copies all the data from the vbk file one more time, and not just the changes from the last backup.
The cause of this behavior is every time the VBR job runs, it updates the file name of the vbk file. This causes Rsync to see it as 2 different files and sends all the data.
Start the registry editor on the server which has Veeam Backup & Replication 5.0.1 or later installed, then:
1. Browse to HKEY_LOCAL_MACHINE\SOFTWARE\VeeaM\Veeam Backup and Replication
2. Create DWORD = DisableVBKRename
3. Set Value = 1
4. Restart Veeam Backup Server
Perform a new full backup and then the filename of the VBK will not change anymore. This will resolve the issue.