Reddit mentions of Seagate 2TB Enterprise Capacity HD SAS 6Gb/s 128MB Cache 3.5-Inch Internal Bare Drive (ST2000NM0023)
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Reddit mentions: 1
We found 1 Reddit mentions of Seagate 2TB Enterprise Capacity HD SAS 6Gb/s 128MB Cache 3.5-Inch Internal Bare Drive (ST2000NM0023). Here are the top ones.
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Sixth-generation drive technology with SAS and sata interfaces for 24 x 7 reliabilityEnhanced error correction, super parity and end-to-end sas-based data integrity for accurate data storageBest-in-class rotational vibration tolerance ensures consistent performanceImproved power and cooling efficiencies with low power consumption and on-demand power choice technology based on T10/T13 power management standardsMulti-drive firmware maximized for enterprise raid system availabilityImpressive 2TB storage capacity for bulk-data applicationsSixth-generation drive technology with 6 Gb/s SAS interfaceBest-in-class rotational vibration tolerance ensures consistent performanceImproved power and cooling efficiencies with low power consumption and on demand Power Choice technologyMulti-drive firmware maximized for enterprise RAID system availability
Specs:
| Color | Silver |
| Height | 1.028 Inches |
| Length | 5.878 Inches |
| Number of items | 1 |
| Size | 2TB |
| Weight | 1.543 Pounds |
| Width | 4.01 Inches |
I would recommend switching from SATA disks to NL-SAS disks as soon as you can - SATA disks have a queue depth of 32, whereas NL-SAS disks have a queue depth of 254.
You'd be surprised how inexpensive nice NL-SAS drives are these days: http://amzn.com/B00AA76GQU?tag=amz-link-20 (I use these and they work great)
I had the "VSAN Nightmare" due to using SATA magnetic disks and a low queue depth, and after moving to a RAID controller with queue depth of 1024 and NL-SAS disks the performance has been fine. You can learn more about the queue depth here: http://www.yellow-bricks.com/2014/06/09/queue-depth-matters/
Luckily your RAID card is fine but I honestly wouldn't trust a production VSAN cluster to SATA disks based on my experience
My environment now is 8x Dell R720xd with 3 disk groups each - 1x 200gb Intel DC S3700 SSD and 3x Seagate ST2000NM0023 2tb 7.2k NL-SAS, behind H710P controller. Machines are connected to 10gbe network physically isolated just for VSAN use.
I had tried at first to screw around with policies in terms of # of disk stripes per object, but ultimately noticed almost no real-world difference in VM performance. After picking up the VSAN book that was recently released, it said effectively, don't screw with the # of disk stripes setting. The only time that changing that policy setting would improve performance (per the book) is if you have a huge amount of read IO to the point that you are outstripping the read cache on the SSD and reads are coming from disk. This doesn't apply to my environment so I ended up going back to just a "1x FTT, 1x stripe" policy as my default (matching the "unassigned" policy default which you shouldn't use), and then a "2x FTT, 1x stripe" for really important stuff.
Truthfully don't have a lot of time for benchmarks these days and our environment is heavily production so I try not to look at it the wrong way; I think in reality, as long as you have properly set up network, good RAID card, fast SSD's, and SAS magnetic disks, you will effectively be playing in SSD cache most of the time and there isn't much more you can do to tweak it.
VSAN is pretty low on customization options, really the ONLY thing you can do is fiddle with the policies, but the experts basically say "dont touch them" and that seems to work for me