> * HPE DL385 G10 Plus
> * Dell PowerEdge R7515
You should also look at machines made by SuperMicro and resold
via a number of VARs. My company is currently using Silicon
Mechanics and is reasonably happy with them. We have a few HPs
as well.
> I have already learned from my local vendor that HPE does not support the
> use of non-HPE HDDs in the server which means I would need to buy all my
> drives directly from HPE (of course this will be very expensive).
It's ridiculously expensive. Also, note that HPE won't ship
empty drive sleds for free. You can buy them aftermarket for
about $15-30 each, depending.
> Additionally, none of the server manufacturers list Debian compatibility,
> thus my questions are as follows:
>
> * Does anybody run Debian stable (10) on any of these servers?
> Does it work well?
Yes, and yes. Avoid buying HP's RAID cards.
> * Is there any experience with "unsupported" HDD configurations i.e.
> disks not bought from the server manufacturer?
They all work.
They tend to be more finicky about RAM.
Buy SuperMicro, from a VAR not too far away from you who can
supply a next-day parts warranty for cheap.