hp proliant – HP DL380e (Gen8) Not showing drives as available

I have a HP DL380e Gen8 that’s not showing 4 (new-to-me) drives in the HP Array Configuration Utility.

There are a total of 8 drives installed to a P420 controller on the latest firmware.

  • 4 HGST 1.2TB 10k SAS drives (PN 0B28482)
  • 3 HP 146GB 15k SAS drives (PN 512544-004
  • 1 Apple 100GB SATA drive out of an old MacBook (for testing purposes only)

The drives not showing are the four HGSTs which I have just bought used. On the caddies, the activity light stays spinning and I think the disks are spinning although it’s hard to tell over the sound of the DL380 fans. But these drives don’t show at all in the Array Configuration Utility.

I have tried the old Apple SATA disk in the caddies to rule out any issues with those, and tried different drive bays that are proved working with the other drives.