KTN-STL3 with 15 x 3TB on the way...how would YOU configure?!


New Member
Sep 25, 2019
Hey Everyone—

I have a couple of EMC KTN-STL3 enclosures on the way with 45TB (15 x 3TB) in each. These will be replacing the RAIDs I have on both of my Mac Pro servers, which host my media archive in 2 different locations. The included 45TB is more than I need currently. My 2 servers currently have:

Michael Scott :):
4 x 4TB RAID 5
12TB usable
10TB in use

Jim Halpert:
6 x 2TB RAID 5
10TB usable
8TB in use

Michael Scott hosts an extra backup snapshot of one of my machines, so that accounts for its extra 2TB used.

The new arrays will be connected to Areca 1880x or 1680ix RAID cards, and I plan to go to RAID 6 for a little extra protection (keep in mind these mirror each other as well). But even then, that would be 39TB available if I used all 15 drives for each...way more than the 8TB I'm using now.

Interested to hear your thoughts on how you'd configure the disks/shelfs if it were you. I was thinking I could possibly use 10 drives in RAID 6 (so 30TB, 24TB usable) and then have 5 spares per enclosure, as well as 5 open bays for utility use. I guess it also occurs to me that while fun to have the maximum capacity showing up and available, it's also easier to expand an array than to downsize it (if I wanted to reclaim some unused bays/drives later).

Thanks for your thoughts!

Jeff Robertson

Active Member
Oct 18, 2016
Chico, CA
Have you thought about selling those 3TB drives and going with larger spinners? $170 ish for shuckable 10TB WD drives would save you a significant amount of power and heat. Not to mention 30 drives gives you quite a few points of failure. Just a suggestion, sound like a fun project no matter how you roll with it!


Active Member
Mar 31, 2018
I had really bad experience with rebuilding times with Raid 5 like systems so you may want to take this into account. How frequently do you update your archive? How frequently do you need to access you entire archive?


Active Member
Dec 26, 2018
The Netherlands, Groningen
i wouldn't use any hardware raid. you maybe better off with software raid, like stablebit drivepool or snapraid.

disadvantage of snapraid is that you have to manually sync and scrub your files.

if your archive is not changeing very often snapraid is good option.



Jan 21, 2013
The arse end of the planet
These are DAS chassis, nothing to do with whatever RAID Controller or HBA. There are some warnings myself and others have discussed witht he EMC drives being 520/528 Bps rather than standard 512. Other than that, simple and cheap enterprise grade dual-port DAS.

As for the configuration, IT mode HBA, dual cabled and SAS drives, you will have issues of the drives being seen twice to the Host. I use HW RAID thus smart enough to know and work.