Faced with the need to migrate 16 external hard drives to a more robust solution, our small IT team went searching for the ideal hard drive array. To us, ideal means inexpensive, reliable, RAIDed and easy to maintain. We support a medium-sized organization, so we have to keep close tabs on resources, including our time. Unlike in my last role as assistant to the IT manager in a financial services company, my current role requires much more attention to the bottom line, too. And since it’s my team who will ultimately have to support the device, reliability and ease of maintenance means a low total cost of ownership. All of this makes our users happy–the role of any IT team when it comes down to it. Ultimately we selected the DroboPro. Here’s why. And if you like what you see, and you want to see more, please consider visiting one of our sponsors. Each click makes us a few cents.
We traversed the search engines (what we do best) and contacted our vendor resources to see what was available. We checked out HP and some of the other more mainstream vendors. By mainstream I mean basically enterprise-level solutions under $50k. The problems we found with these solutions were that most of them didn’t support the largest size hard drives on the market yet. Specifically, most of them didn’t support the new Western Digital 2TB Enterprise class drives. They’re green, so they run a little bit slower than other drives; but WD drives are pretty reliable, or such is my experience. One highly annoying caveat from this search is that a lot of HP’s arrays take the smaller Ultra320 SCSI drives, which, at least to my knowledge, don’t come in sizes larger than 300GB. Please correct me if I’m wrong on this, but I haven’t found Ultra320 SCSI’s bigger than that.
We’ve used the smaller 4-bay Drobos for many months for workstation backups, and we’ve been really satisfied. So when we found the DroboPros, we were anxious to look into them. Drobo has some really, really nice features. On our older Drobo’s, as well as the DroboPro, they use a technology that they call BeyondRAID. RAID 5 protects an array in case of single drive failure, RAID 6 protects the array in case of two disks failing simultaneously. Their BeyondRAID technology also offers some neat self-healing, drive reordering and automated (gasp) management of mixed drive sizes, upgrades, etc. Normally I’d shy away from these features and opt for managing the array myself, but I’ve seen it in action, and it actually works quite well.
Check this out. Right now the biggest hard drive you can get is 2TB. Many enterprise-level arrays won’t even support this. Most of them only support up to 1TB because, as is the nature of enterprise hardware, it can be a little slow to catch up. Almost all of the larger arrays we checked out–those that support 30 or more hard drives–don’t support anything bigger than 1TB. The other issue here is that with the traditional model of hard drive array, once you pick a drive size (sometimes even a drive make/model) you are stuck with it. Say you have a 30-bay array with 30 1TB drives and you’re ready to migrate up to the 2TB drives and double your space. If your array will support these larger drives, which is not likely, you’ll have to reconfigure the entire thing.
When you’re ready to upgrade the DroboPro (as well as a smaller Drobo) from an array of 1 or 2TB drives to the inevitable 4TB, 8TB or 16TB drives, you simply remove one of the drives and replace it with a larger one. It’s hotswappable. And, get this, the data on the missing drive is still accessible while the device formats and prepares the new larger drive. Furthermore, the drive sizes don’t have to match. You can have a Drobo array with mixed-size drives from 1TB to 16TB. This means that in the 8-bay DroboPro I can ultimately have an array of 128TB of space assuming I don’t want single or dual disk protection. Yes, you get that option, too.
Another thing to consider is your connection to the unit. It supports USB, FireWire800 and, my favorite, iSCSI. When we got our first two DroboPros, we filled them with 8 2TB hard drives each with RAID level 6 for that dual-drive protection. We hooked them up via FW800 and began simultaneous transfers from 2 1TB external Glyph drives to each of the drives. It was a straight copy of all the drive contents from each Glyph to one of the Drobos. This way we wouldn’t eat up too much of either connection’s resources.
At first we were pretty disappointed. It was taking at least 13 hours to transfer the drives simultaneously. So we took it down to one transfer, and our time dropped to 4-7 hours for 500GB. Still not that great. To make matters worse, the transfers seemed to tank ultimately. Almost none of them finished in one transfer. We had to come back and restart the transfer after a few hours because the Drobo would lose its connection–or something. Also our throughput was something like 2MB/second, which is terrible. I noticed that whoever attached the Drobos to the server had pinched the cables pretty good. That could have been the reason. Nevertheless, I called Drobo’s tech support–the real test.
I spoke primarily to Jeremy, who was not only extremely helpful, but he was really friendly and thorough, too. He identified that we were not on the latest firmware nor did we have the latest Drobo software–the application that runs in the background. Also he had me test some different cables on the devices to troubleshoot the connection weirdness. He asked why weren’t using iSCSI. I didn’t install the device, so I was curious too.
It turns out that iSCSI is really easy to setup on these DroboPros. And it works great. Dig this. You simply plug a Cat5 ethernet cable into the DroboPro port and the other end into your server. If you don’t have dual network ports like we do built in on our Macs, just get a gigabit switch and network the Drobos like you would anything else. The Drobos are given DHCP IP addresses. More or less plug and play. By the end of the day, we had the units reconfigured for iSCSI. We were transferring up to 3 Glyphs at a time in about 3 hours with about 45MB/second transfer speed. Now that’s impressive. Oh, by the way though, your iSCSI needs to run on a gigabit network otherwise the speed isn’t going to be much better than FW800.
A couple weeks have passed, and we’re still quite pleased with the DroboPros. At this point, I highly recommend them. I’ll update this post if my opinion changes. But in this price range there doesn’t seem to be anything better. The DroboPros are around $1500 each. The WD 2TB enterprise hard drives are about $320 each. Our cost per TB is roughly $340 after RAID (which eats a few TB).
