Yellow Bricks

by Duncan Epping

30K for a VSAN host @theregister? I can configure one for 2250 USD!

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I’ve been following the posts from the Register on VSAN and was surprised when they posted the cost of the hosts they configured: 30K each. With 3 at a minimum they concluded that for 90K you could buy yourself a nice legacy storage system. I don’t disagree with that to be honest… for 90K you can buy a nice legacy storage system. I guess you need to ask yourself first though what you will do with that 90K storage system by itself? Not much indeed, as you would need compute resources sitting next to it in order to do anything. So if you want to make a comparison, do not compare a full VSAN environment (or any other hyper-converged solution out there) to just a storage system at it just doesn’t make sense.

Now that still doesn’t make these hosts cheap I can hear you think, and again I agree with that. Although I have absolutely no clue where the 30K came from, and judging by the tweets this morning most people don’t know and feel it probably was overkill. Call me crazy, but I can configure a fully supported VSAN configuration for about 2250 USD (just HW) on the Dell website.

  • Dell T320
  • Intel Xeon E5-2420 1.90GHz 6 Core
  • Perc H310 Disk Controller
  • 32GB Memory
  • 1 x 7200RPM 1TB NL-SAS
  • 1 x 100GB Intel S3700 SSD (or dell equal drive)
  • 5 x 1GbE NIC Port

I would like to conclude that VSAN would be a lot cheaper than those legacy solutions, less than 7500 USD for 3 hosts is peanuts right?!? Yes I know, the above configuration wouldn’t fit many use cases (except for maybe a ROBO deployment where only a couple of VMs are needed) and that was the whole point of the exercise showing how pointless these exercises can be. You can twist these numbers anyway you like, and you can configure your VSAN hosts any way you like as long as the components (HDD/SSD/Controller) are on the VSAN HCL and the system is on the vSphere HCL. PS: Dear Register, next time you run through the exercise, you may want to post the configuration you selected… It makes things a bit clearer.

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Comments

  2. $7500 for 3 nodes produces how much usable storage?

    1 x 7200RPM 1TB NL-SAS
    1 x 100GB Intel S3700 SSD (or dell equal drive)

    Depending on your “host failures” option within your VM policy – this can range from $3750 per TB up to $7500 for 1 TB of storage (assuming “Failures to tolerate = 1″ or “Failures to tolerate = 2″).

    And this assumes the working set for acceleration is happy with 100 GB SSD – if the application has a larger than 10% working set – I would assume costs could up with larger SSD drives per Storage Node.

    And that’s just the hardware costs – add $2,500 per server for a VSAN software (and I think this is MSRP – so actual pricing may vary on ELA or non-ELA pricing terms) and then add on some hardware and software support costs.

    So it could push north of $3750-7500 per TB.

    $2500 Storage Controllers are certainly less money than $30k Storage but I think the metric that folks pay attention to is the $ per TB.

    I also assume The Register did fully loaded Storage Servers (14-24 disks) to compare it with “the cost of a new, fully-populated, disk drawer is not far from the cost of a new VSAN node.” and likely to have used SAS drives vs. your lower-cost SATA drives.

  3. What point did I miss? That you used a Dell T320 and its not on the approved list?

    http://www.vmware.com/resources/compatibility/search.php?deviceCategory=vsan

    The Dell T620 is the only tower up there (unless its not curent) (was it a typo?) and its the Advanced model from Dell (the T320 was the basic and T420 was in between little bear and big bear).

    I think I got that you wanted to call out that a VSAN storage node doesn’t have to cost $30k – got that loud and clear and I agree with you – folks are running 3-node ESX clusters with Intel NUC boxes or Mac Mini Servers.

    I hope I didn’t miss the point that you can build a storage controller with:

    1 x 7200RPM 1TB NL-SAS
    1 x 100GB Intel S3700 SSD (or Dell equal drive)

    Dell’s got two different types of SSD which I found interest – Value MLC (200, 400) and then Read Intensive MLC (160, 300, 480) – so I assume they different DWPD metrics – I didn’t see the 100 GB in the Server Components – maybe its in the tower components.

    The Value MLC was more money – so I bet its a 10 DWPD (?) and then assume the Read Intensive MLC is the 1-5 DPWD.

    Which type of SSD did you use?

    Also – do you know what you used for RAM? Was it a UDIMM? RDIMM? LRDIMM? I went with RDIMM.

    The VMware compatibility list only had the 400GB SSD SAS Value SLC as usable so not sure how you can run a 100 GB in there.

    I added an extra metric on there for the “cost per TB”.

    Because if you did build a $2500 controller node and need 3 of them for high availability – then its $3750 per TB for 2 TB usable (1 host failure) or $7500 for 1 TB usable (2 host failure) – right?

    For the T620 – I ended up with a MSRP of $4,300 per node (Instant Savings took it down to $3200) or $12.4k for 3 nodes (instant savings of $9.6k)

    So that would be $4800 per TB for 2 TB usable (1 host failure) or $9600 for 1 TB usable (2 host failure) – right?

    I didn’t see The Register article saying how many TB any of their $30k flavor was – so if you are just comparing CAPEX for the sake of CAPEX – then sure – you can build a Dell Tower with 2 HDD cheaper than a Dell Rack with 24 (the big unit had 24 HDD slots).

    Did The Register even post their configs? Or usable TB?

    • I really think people are having a difficult time understanding the compatibility list. Just because a system isn’t on the “Virtual SAN Ready Node” list, does not mean it is not supported with VSAN. It just means it isn’t a ready built config. You can easily build a T320 with a compatible controller and compatible drives and have a supported configuration. It just won’t be a “Ready Node”.

      The point of this article is that just like everything else… The answer is… it depends. Will VSAN be cheaper? It depends. Will it perform better? It depends. There is no silver bullet with VMware or any IT system. Every companies needs are different.

      What’s important though is to compare different “complete” solutions side by side and weigh the pros and cons. A VSAN is not just a SAN. It is a complete hardware solution. When comparing it to a SAN you need to factor in compute, storage and connectivity (something everyone is leaving out).

      To squabble over $$$ per TB isn’t the answer. The answer is to understand the value of all solutions and recommend\purchase the one that makes the most sense based on your particular need. Just be sure you are comparing apples to apples.

      • The answer to anything complicated is “it depends”.

        Metrics like cost per TB aren’t end all / be all – but they help with evaluations – the whole point of Duncan’s block was that a VSAN node didn’t have to cost $30k.

        And I agree with you, you work hard at it – you can install ESX on just about anything – but you aren’t going to run that MacBook Pro with ESX on it in Production.

  4. Both you and Rob are indeed talking the same, what could be done is to have more white papers or you could write about running a business critical application on VSAN and publish a table with comparison stats cost,price per tb, performance, about what it would have cost if some body to do it on VSAN vs doing it on a storage. A better way could be that we could have tool/webpage to do the same

    • Why not use the VSAN assessment tool to profile the workload and identify how to configure a VSAN so the flash takes care of 90% of all IOPS (Cache hit rate). The tool pulls SCSI traces and actually identifies how many hot blocks there are during the 10 day monitor period, and you can imput your existing SAN cost per GB usable (grab your old invoices) and then the cost for flash your going to buy and the disks your going to buy and it does a full comparison for you. Its really surprising how little at the block level VM’s are active…

  5. Just for a side note, for my home lab I nest ESXi inside VMware workstation. (You can do the same inside ESXi). In doing so, you can emulate an SSD in the VMX file and use that to create your vSAN on your hosts.

    Cost me jut over a $AU1000.

    Great price for physical hardware Duncan.

  8. I think a simple way to compare VSAN costs vs. traditional storage would be to only include the cost for the additional drives, NIC and the VSAN licensing. That way you assume that the cost of the server (and related support costs) are already paid for by the need for compute resources.

  9. Just a note… you might want to add a update/caveat to this post now that the H310 has been removed from the HCL. Thanks Duncan!