This is a hack to add an extra bay to a Dell Server. Tried with both PowerEdge R230 and R430.

Replace DVD w/SATA Bay. They make replacements for laptop DVD bays that allow you to put a second sata drive there instead.
This replacement part can also drop right in place of the slim DVD bay on a Dell PowerEdge. I’ve seen multiple references to this setup working. This guy’s blog has screenshots of it. https://tachytelic.net/2019/10/install-ssd-optical-13th-generation-poweredge/

I don’t see the disk. At all. The OS doesn’t. PERCCLI doesn’t see it. iDRAC doesn’t.
When I got into Lifecycle Controller to manage the disks, It used to see the SATA DVD drive at the end of the list, but now there’s no entry. (On the R230 when I removed the drop-in and put the original DVD back, it went back to normal. The bay is in the R430 right now.)

I’ve got the right bay, it fits. More important, the electrical stuff all matches up. The drive light activates. Got a brand new drive in there. It hasn’t been tested otherwise, but I’d like to think its ok. In the post I’ve linked, it looks like he has his SATA set to ATA, not AHCI, so I tried that, but no change. Poked at it quite a bit. Can’t think of anything else to examine.

Alright … so there’s all the setup. And here’s why I think it doesn’t work. My main disks are all SAS on both machines.
R230 PERC H330 - 4 x SAS 7.5k 3.5" spinners R430 PERC H730 mini - 6 x SAS 10.5k 2.5" spinners

I’ve read that you can’t mix SAS and SATA drives. As the DVD seemed to be a normal SATA, I figured I could use that port with a SATA SSD. But maybe not. It’s not worked on either server, and all the gear involved appears to be operational. It’s worked for other people. But every reference I’ve seen to this working seems to be all SATA setups.

Does anybody know for sure?