The CubedHost Operations team has been informed of two failing drives via automated monitoring in this system with RAID10.
The second failing drive (sdd) is non-critical and can be replaced in 24 hours. The first drive failing (sdc) is critical and has been replaced immediately.
The RAID array is now rebuilding; estimated 12 - 16 hours rebuild time.
Update: The sdc drive has been replaced and the RAID array has been rebuilt. We will perform a replacement on sdd Monday night.