Hi,
for quite a while I'm trying to find out why hard disks do not spin down after the set time with DSM 6.x and ESXi Hypervisor (6.0 or 6.5) using Jun's loader.
Hard disks are connected to a passthrough SATA Controller (onboard, also tried PCIe). Exactly one and the same setup is working bare metal, also with DSM 5.2 on ESXi. I even tried using a boot iso (as with DSM 5.2) that uses the passthrough USB boot stick (like with bare metal) instead of synoboot.vmdk/synoboot.img combination. No spindown, hdparm -y does a spindown, however disks wake up at once again. I can't see any differences in the logs between running bare metal or on ESXi.
Would appreciate any further ideas.