I’m working with vSphere4, your OpenSolaris solution sounds interesting although I’m a little bit worried about the further development of OpenSolaris since Oracle bought Sun

That is disappointing. The more spindles (more drives) you have in an array the quicker it should respond to IO requests, assuming that the array is configured correctly, the correct drivers are installed for the controller and the iSCSI target software is working properly. Data Robotics is likely trying to create their own iSCSI target software, or some variant, and QNAP might be using a well known iSCSI target such as IET or Open-iSCSI (IET is used by OpenFiler).

Although I think that Data Robotics could make their product faster, I do think that VMware complicates the matter by implementing some unique SCSI calls (or unique methods) that allot of iSCSI targets have a difficult time processing. This has something to do with VMFS. Try the Microsoft iSCSI software initiator to your DroboElite and I bet the performance will be 10 fold. However, it still doesn’t resolve the issue with cheap shared storage for VMware. Are you using the latest ESX or ESXi?

If you are ambitious, take a look at my OpenSolaris iSCSI article and make your own.

-Aaron

I’ve bought the DroboElite 2 month ago. Performance under VMware with VMFS is quite disappointing. (8 Seagate HDD’s a 1.5TB inserted). I also own a QNAP 509 NAS as a fileserver and made a test for fun, exported an iSCSI Target to my ESX host. The performance with only 4 HDD’s!!! was better (I/O’s & MB’s per Second). It seems to be the case that more HDD’s won’t give you more performance. A workmate has a QNAP 859 equipped with 8 HDD’s, through iometer he got over 10000 I/O’s per second, my DroboElite is only able to server max 2500 I/O’s per second…

Another thing that is annoying is that the 2 iSCSI Ports can’t be bonded together. So when you are backing up your machines through e.g Veeam Backup & Replication it can happen that the ESX hosts looses the connection to DroboElite. At the moment all my machines in my lab have moved to local storage until this issues are fixed, already thinking about to sell the Drobo…

Stephan

When I purchased the DroboPro, the DroboElite was probably still in development. Not to be too contradictory with a product manager at Data Robotics, if I remember correctly, the documentation for the DroboPro states which iSCSI TCP port to use for multiple connections. Although the design is spectacular and the management application is neat, the disappointing fact was that the DroboPro was supposedly VMware certified. To be honest, this seems like more of a problem of VMware’s certification program; however, the engineering department at Data Robotics should have spent more time with ensuring a solid solution with VMware if they were hoping to produce an exceptional SMB VMware storage solution.

If I had some money, I would love to try the DroboElite with VMware to see how well it works.

-Aaron

The DroboElite is the rigth solution for your SMB VMware storage solution. The DroboPro is really designed to connect to a single server only. The DroboElite is our multi-host iSCSI SAN solution.

As the DroboElite is being implemented into more and more complex VMware environments more and more stress has been placed on the system. We have discovered an issue with our firmware that causes the DroboElite to disconnect from the VMware ESX clusters while under heavy load. We have been able to reproduce this corner case in our labs and we currently have a fix in place. This fix is currently under internal test and is also being tested by a handful of external customers that have experienced this issue. The testing results have been very postive to this point and we are projecting a general release of the new DroboElite firmware within the next several weeks once we complete our specific testing surrounding this issue as well as complete our general regression testing required for all general release firmware.

Brad Meyer
Product Manager – DroboElite

I would agree that VMFS and/or the VMware software iSCSI initiator cause issues with the DroboPro (haven’t tried the DroboElite). The part that I find interesting is that the product is supposedly VMware certified. Although it is great marketing for Drobo, it makes one think: what type of certification requirements does VMware have?; and does Drobo realize that by being VMware “certified”, yet, “incompatible” with VMware, that their marketing plan is having a reverse affect?

From my experience, the reality is that there are no inexpensive and stable iSCSI storage devices on the market yet. iSCSI must be too new for all of the quirks to be worked out – especially with VMware and it’s unique filesystem.

-Aaron

Dell R610
Drobo Elite
Dell Powerconnect 2724

- jumbo frames enabled start to end (vswitch, vmnic, vmkernel), on the switch, and on the Drobo Elite

Doing an upload/download from a Windows 7 workstation to the Datastore on the Drobo yields about 20MB/sec throughput (as reported by Windows). A similar upload/download to a normal file server jumps upwards of 80MB/sec.

I thought performance would be a little better than that…