Best high-availability, active-active (dual controller) rack storage for Virtualisation

ES1686DC to replace out SAN

Hi! I have watched several of your videos and really appreciate all that you do. We currently have a 3-host (with failover) ESXI 6.5 setup (with vsphere 6.5) with about 25 VMs running on it. Only a few of the VMs are high volume traffic of large case files of a small department and the rest are smaller duty microsoft sql servers along with our organization-wide windows file server. Some of these VMs are very high priority for public safety functions so we are quite uptime-dependent. We have been running our vsphere environment via iscsi into our Infortrend DS1016 SAN unit. This unit has been OKAY for the five years we have had it deployed but it has lost two controllers in the time being. Being that it has been done under service contract, we never know what the exact cause of the failures are. We have been thoroughly unimpressed by the units’ inability to truly be a high-availability system it is advertised to be, controller replacements have now twice required the whole SAN to be shut down in order to match up firmwares of the two controllers, etc.

We are really hoping that a Qnap ES1686DC unit can hold out and be a better solution that a typical SAN that normally comes with extremely expensive service contracts and warranties. The included software licenses, functionalities, warranty, etc of a QNAP system is very enticing.

We would love to hear from the experienced just how enterprise these enterprise qnap systems really are and if the iscsi latency of these units is feasible for a well working VM server environment.

We do plan on utilizing our 10gig core switch to pair the hosts and QNAP together via teaming or bonding if need be. We are also interested in running SSD cache on the QNAP itself. What we do not know is if a cache drive failure can take down the storage volume or not, I would figure that it being dual controller, if one of the SSDs fail in a controller, operations continue as normal.

Any input we can obtain about the enterprise qnap products used mostly as an ISCSI datastore for a VMware environment would be so helpful. Thank you.


Infortrend has always been a budget option, but you are right, warranties and services cost a lot. There are more professional options from Qsan, but you might also pay quite a lot on services. You can have a look here :
But Qnap active-active models are quite impressive. They do stand out with their software just like Synology with their dual controller models like UC3200.
Qnap is more configurable and you will find better hardware in Qnap. Synology is easier to use and they might have more of their own created software which works more symbiotic with the hardware. Here is one of their trade show:
Here is Qnap made tests maybe you find them useful:
Also Storage review guys have made some tests on similar model :

Qnap and Synology are most innovative NAS brands out there today. They add more functions and fixes every day. They also have support centres around the world. Both of these will make a good purchase.

Regards to cache- it only keeps a copy of the most frequently accessed data. Failure will not damage your volume. In fact SSD cache can also be set up as RAID to keep this going too.

I hope this helps.

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