I have 12 14TB WD drives. 4 are shucked (used for a backup pool). 4 are WD Red Plus. 4 are "new" refurbished Ultrastar HC530's. I've just recently created a 8x RAIDz2 from the Reds & Ultrastars. All are in a DIY case with either a 8x SAS2308 or little 4x SATA card, though the symptoms occur regardless of which the drives are attached. TrueNAS Scale (latest stable).
So the symptoms are a "clack" head seek every 5 seconds but ONLY on the Ultrastars. I can remove each of the 4 drives Ultrastars in sequence and it continues, so I don't think it's just one of them (i.e., likely not a defective drive issue). Though I may not keep it this way, at least for experimentation I've got APM and spin down enabled on all 12, and the other 8 will spin down; Ultrastars not so much. Moving all four between backplanes and between controllers...same deal. Export the pool...clacking stops. There are no running tasks and I don't really think this is actual disk I/O on the pool since the other 4 in the array will spin down while the clacking continues.
I'm at a loss to explain it with my limited knowledge. I don't mind the lack of APM, but the clacking worries me. And drives me insane since it's quite audible in an otherwise near-silent build. Is this just an enterprise drive thing? Is there an easy fix?
Checking here before going to the iX forums since you guys tend to be a bit kinder to the less experienced among us.
So the symptoms are a "clack" head seek every 5 seconds but ONLY on the Ultrastars. I can remove each of the 4 drives Ultrastars in sequence and it continues, so I don't think it's just one of them (i.e., likely not a defective drive issue). Though I may not keep it this way, at least for experimentation I've got APM and spin down enabled on all 12, and the other 8 will spin down; Ultrastars not so much. Moving all four between backplanes and between controllers...same deal. Export the pool...clacking stops. There are no running tasks and I don't really think this is actual disk I/O on the pool since the other 4 in the array will spin down while the clacking continues.
I'm at a loss to explain it with my limited knowledge. I don't mind the lack of APM, but the clacking worries me. And drives me insane since it's quite audible in an otherwise near-silent build. Is this just an enterprise drive thing? Is there an easy fix?
Checking here before going to the iX forums since you guys tend to be a bit kinder to the less experienced among us.