I was asked why Data Recovery was only running one single job at a time instead of multiple concurrent. After some investigations I found out that the administrator changed the configured memory for the appliance to 8Gb where 2Gb is the default.
The Knowledge base article clearly states the following about this:
This issue may occur if the configuration of the appliance is modified. Except for hard disk configurations, VMware recommends that you do not change the virtual hardware settings on the appliance. The changes that are not supported by VMware include, but are not limited to, the following:
- CPU configuration
- Memory configuration
- Network interfaces
After reconfiguring memory for the appliance with 2Gb the issue was resolved and multiple backup jobs were running concurrently.