Question

I'm considering getting a fully loaded Drobo Pro and using it to store VHDs that would run our on a pair of Hyper-V host machines. The host machines would connect to the Drobo Pro via iScsi.

Anyone have experience with the Drobo Pro and Hyper-V? My main questions/concern is about speed - is the Drobo fast enough to handle say a dozen VHDs all running concurrently?

jon

Answer 1

Greetings,

I am on the Product Marketing team at Data Robotics, so I'm hoping I can shed some light on the questions around the DroboPro, performance, and virtualization.

Regarding DroboPro performance, there are a few independent reviews that have posted performance numbers. One is GeekBrief.tv and the other is the LA Final Cut Pro User Group.

This site will only let me post one link, so here is the LAFCPUG review and the Geekbrief one can easily be found at Geekbrief.tv

http://www.lafcpug.org/reviews/review_drobopro.html

Feel free to check out the full reviews. In terms of iSCSI performance, LAFCPUG used a tool called Blackmagic and saw ~80MB/s read and ~70MB/s write. GeekBrief.tv used a tool called AJA and saw ~74MB/s read and ~79MB/s write. Burst speeds will certainly be higher as darthcoder alluded in his post, but 80GB/s is close to the limit in terms of sustained throughput on a single GbE.

One thing to note in the Geekbrief.tv review is that there was no mention of attaching the DroboPro directly to a switch which is very easy to do by simply assigning a fixed IP via the USB management port prior to attaching the switch. The latest version of our Dashboard management software has support for multi-host and up to 16 x 16TB virtual volumes.

Regarding virtualization, Data Robotics is in the process of certifying the DroboPro with VMware ESX which is the top priority due to market share. Having said that, we will be doing similar certifications with Microsoft Hyper-V and Citrix XenServer once the VMware certification is complete. While we have not yet officially performed testing with Hyper-V or Xenserver, we are aware of several customers that are successfully using Drobo and DroboPro with VMware, Hyper-V, and Xen.

In regards to your question of whether or not DroboPro is fast enough to handle a dozen VHDs all running concurrently, it should work just fine, but it really depends on the workload.

Hope that helps clarify things.

Regards,

Jim Sherhart

Answer 2

Over a gigabit ethernet connection, you're only going to get a maximum of 120MB/sec. And that's best-case, you'll probably top out at 100, and that's even if the Drobo can keep up with that (though I've heard it can).

I've used iSCSI from an EMC Celerra over the same transport - it did relatively well for 10 or so low-usage hosts, 1 SQL server doing maybe 250-500tps and a Clearcase server doing probably triple that.

Answer 3

Multi-host support is in the 1.1.1 firmware that is now available for download:

http://www.datarobotics.com/support

The intent of iSCSI on the DroboPro was to be a simple, fast interface. Hence the emphasis on direct connections and single host configurations. The multi-host support is really intended for advanced Windows users as you need to be familiar with the Windows iSCSI initiator, Windows disk management utilities, and LUN mapping (i.e. sharing LUNs between hosts is very bad).

The first host will connect on Port 3260 and subsequent hosts will connect on port 3261. This can be configured in the iSCSI initiator (Discovery tab -> Add New Target Portal).

This could also be done on Mac, but not with the free initiator that we include with the DroboPro. It would require the Atto initiator or similar.

Hope that helps,

Jim

Answer 4

Personally until there's more information out there on the Drobo Pro's I would avoid them. The regular Drobo is not enterprise grade equipment and has lackluster performance. I would have to be convinced that the Pro is up to enterprise grade before deploying it in a production environment.

I know a while back on the Xen mailing list there was at least one thread with a user trying to use a Drobo Pro for the storage for Xen Virtual Machines. And they were running into IO errors with it. So you may or may not run into the same or similar issues with Hyper-V. So be prepared to do some testing.

Answer 5

Jim, you mention "multi-host" support is now available. Does this mean that a single DroboPro can be connected to multiple servers simultaneously?

Answer 6

Does the new drobo pro firmware support iSCSI-3 persistent reservations for failover clustering? (for use with Hyper-V failover clusters) I know that none of the value priced iscsi solutions seem to support that at this time. If it does now that's huge for us. (and a sale for drobo)

Answer 7

Hi Jim, Great information. I'm looking for confirmation that the latest revision of your FW supports multi-ESX iSCSI hosts. I have been playing with this for a few days and cannot seem to get the second ESX host to connect reliably to the DROBO (even when setting the iSCSI port on the second host to 3261). I initially saw the DROBO volumes on the second host, but after rebooting the host I could no longer see the iSCSI storage. Thanks, V

Answer 8

Barden - Just checked with some folks in Engineering and unfortunately we only support iSCSI-2 at the current time. Once we complete the VMware certification, we will be looking into Microsoft certification which would include Hyper-V.

V - If you are running firmware v1.1.1 this feature should work, but will not be officially supported until we have completed VMware certification.

Jim

Answer 9

I was wondering - we have a Drobo PRO, and are having real problems running XEN when we load the XEN drivers which use LVM. The unit goes into standby. Are there any fixes or patches for this issue? Any further date on XEN certification?

Thanks

Answer 10

Hi,

in reply to Jim Sherhart from Datarobotics: "In regards to your question of whether or not DroboPro is fast enough to handle a dozen VHDs all running concurrently, it should work just fine, but it really depends on the workload."

I purchased a DroboPro with 6 x 1,5 GB two weeks ago (Firmware: 1.1.3 / 2.39.21543). We are running Windows2008 R2 x64 and DroboPro is connected via iSCSI. Performance while copying files from local harddrive to drobo is very good, 80 - 120 MB/second.

But: Performance of Hyper-V (VHDs placed on DroboPro) is bad. Support from DroboPro confirmed that there are known issues with Hyper-V. I have to wait for the next firmware update. :-(

Best regards Michael

Answer 11

I can second Michael's statement that the DroboPro works well with Windows hosts and am seeing the good file copy numbers he is seeing.

The bad news is that we are trying to use the DroboPro to house VMWare ESXi 3.5 datastores and are seeing poor performance in that use case. We've configured the DroboPro per the VMWare best practices whitepaper, have it filled with 8x750 Gb 32 meg cache 7200 rpm Samsung drives with double parity on the storage and are getting substandard VMWare performance. We haven't been able to get much more than 10 MB/second despite the direct connect 1Gbps full duplex network connecting the DroboPro to our Dell PowerEdge 2900 ESXi server.

After 10 days of troubleshooting with support the answer we were given was "In regards to the performance issue, this will require a firmware update on DroboPro. This is currently being worked on and we hope to release jan/feb. time frame."

Regards, Doug

Answer 12

Very glad i found this thread. I'm also thinking about getting a drobo pro to run VMs. I have two powerful desktops running linux Debian and vmware server 2, but I want the added security of RAID. I will make a purchase soon, hope that drobo gets the new firmware and bugs out... or ill go internal adaptec... got my eye on you

Answer 13

I bought a 4TB Drobo Pro to run hyper-v for some of my development boxes. I'm using the iSCSI interface, and carved the drives up into 3 1GB partitions. I get good performance copying to and from the drobo, but as others had said the hyper-v performance is quite bad if you have a heavy IO load. I've been able to make it usable by moving some of the .vhd files to the different partitions.