This article describes troubleshooting steps to take when agentless backups do not recognize all attached disk volumes.
When adding a server to a Datto device, only the C volume is recognized by the Add Agent Wizard. Volumes contained on other virtual disks and partitions are not recognized by the wizard.
Diskpart shows the disks set to online. There are no volumes set to hidden. Secondary volumes are attached to the VM using the same method as the C volume. All .vmdks have the same naming convention.
Datto appliances can fail to recognize agentless disk volumes when all disks use the same naming convention. This is because all agentless metadata for the protected system will appear to point to the same image file. To correct this issue, Datto recommends that you identify each .vmdk's datastore in its name - for example, the name CCRFS01-P.vmdk indicates datastore CCR for FS01's P volume. Assigning unique names to each volume will help the Datto appliance differentiate between VMDKs.