Dell PowerEdge server R730

A "VD 0 (Degraded)" message in your Dell PowerEdge server BIOS indicates that a virtual disk (VD) in your RAID array is in a degraded state. This typically means that one or more of the drives in the RAID array have issues, and the array is no longer in an optimal, fault-tolerant condition. Please check the following:

• Check the RAID configuration in the BIOS to ensure that the new SAS SSD is recognized and included in the array.
• If the new SAS SSD is not recognized, try reseating it or checking the cable connections.
• If the new SAS SSD is recognized but the VD 0 (Degraded) message persists, try rebuilding the RAID array using the RAID controller software or the BIOS utility
• If the RAID array cannot be rebuilt, it may be necessary to replace the failed disk with a new one and rebuild the array from scratch.

Hope this helps. 

Within a diskgroup(raid set) only devices of the same type can work together. I have my doubt that a SSD can be part of a HDD diskgroup even if the SSD have the same or larger size.

Regards,
Joerg