So I purchased a bare DroboPro FS and 4 3TB Western Digital hard drives.
The first thing I did was download the latest Drobo Dashboard ( version 1.1.1 ) from the website, after installing I proceeded to hook up the DroboPro FS to my network.
Using the Drobo Dashboard I updated to the most recent firmware before even inserting any of the hard drives.
I installed the hard drives and finished configuring the DroboPro FS through the Dashboard, so I am now all set up.
Here is where the problems occur…
I start copying folders over to the DroboPro FS, at first I was getting write speeds of 32-33 MB/s and read speeds of 57-58 MB/s .
After I finish copying a few folders ( checking read & write speeds after copying each folder) I end up with a total of about 10 GB loaded onto the DroboPro FS and my read speeds drop down to about 20 MB/s.
If I keep loading the DroboPro FS with data, say a total of 3 TB my read and write speeds drop down to about 4 MB/s.
This is my network setup.
DroboPro FS attached to a 10/100/1000 D-Link switch which is attached to a 10/100/1000 D-Link router and the computer used for testing is attached to the router, all using cat 6 cable.
I’ve ruled out the possibility that my network could be at fault by directly attaching the DroboPro FS to the computer using a different cat 6 cable, also tried a cat 5 cable just to be sure the cables were not at fault.
With the DroboPro FS directly attached to the computer I may have gained between 2-4MB/s…this brings me to a total of about 6-8MB/s transfer rate.
The computer initially used for testing is running Windows 7 Ultimate 64 bit operating system.
I tried resetting the TCP/IP networking stack since that had helped some users but it didn’t seem to make a difference.
So to rule out the computer as the problem I tested on another Windows 7 computer and got the same results.
To rule out the operating system I tested the DroboPro FS directly attached to an iMac, still same results yet!
The only suspects left to blame is the DroboPro FS it’s self or the hard drives…
I tested each hard drive individually with the DroboPro FS and using Western Digital’s Diagnostic software with the drives installed in a computer.
I also disabled to idle timer on each drive to prevent the drives from auto idling.
To rule out the drives all together I tested 2 1TB 7200 RPM Seagate drives inside the DroboPro FS… same problem as before.
So what’s left to blame, the DroboPro FS.
After communicating with Drobo support and performing numerous read & write benchmarks along with submitting logs over a 2 month period Drobo support sends me a Drobo B800fs, the business edition of the 8 bay Drobo FS models.
Well the Drobo B800fs is showing the same results as the DroboPro FS and it does not have any firmware updates available for it at the time of writing.
So I am looking to you Drobo users for support.
If I am able to achieve write speeds of around 55 MB/s and read speeds of around 60 MB/s while the drives are empty should I not be able to achieve close to these speeds with data on the drives, even if it’s just a small amount of data?
Do the Drobo units need to have all drive bays full of drives in order to maintain good (or what is good for Drobo) read and write speeds?
Am I overlooking anything?
Is this just expected behavior of a Drobo?
Sorry for the lengthy post however I felt I should include as much detail as possible as I have worked on this issue for the past couple months and I am ready to fix the problem or find another product.
Any comments or suggestions are welcome.