4 Bay Drobo with front panel removed. Status lights showing 4 drives are running OK and the blue lights show 40% capacity used
I am writing this article as a major revision of a review I wrote on Amazon several years ago as it was looking dated.
I have been using Drobos for more than 4 years. One of my units is the now discontinued 4 bay USB model. The other is the 4 bay Fire Wire 800 model. As a user who has lost replaceable data on these units I believe my insights are going to be a bit more “real world” than most reviewers who encourage you into these systems while not really using them for lengthy periods.
Firstly why RAID storage?
If you are storing anything on a hard drive you stand a chance to lose all data on that hard drive when that drive fails. Briefly a hard drive is made of a magnetic platter spinning around about 100x per second. Data is read by a hard and sharp head that skims less than a hairs width above the platter. A sudden jolt, as little as toppling a hard drive resting on its side edge onto a table, can be enough to force contact between the platter and head. The furrow the head will cut into the platter will destroy all data at point of contact. At 100 revolutions per second this can mean a lot of data. The metal filings scratched from the platter then become “dust” skipping all over the hard drive whenever it is on, thereby causing abrassive damage to the rest of the drive over time. These turn up as bad sectors and again, any data underneath these areas is lost for good. Last of all, the heat from the computer, and the electric moter inside the drive create heat. Highschool physics teaches us that heat and magnetism don’t mix. To cut to the chase. Your hard drive WILL fail eventually.
To avoid losing data several solutions exist. These include backing up data, and setting up a cluster of discs set up in RAID array. A RAID array is usually configured to perform one of two things. Speed up data transfer (there are some very risky ways of doing this) or the more normal redundent array, which means that if a hard drive fails your data is already safe on another disc. As multiple hard drives ARE heavy, people like their bulk storage to be in its own dedicated enclosure otherwise their desktop or Notebook gets a bit heavy and certainly cumbersome to lug around.
There are a few solutions around. I have until recently been using DROBOS and Freenas 8 with ZFS. I may write a more extensive review of my experiences with FreeNas and the superior ZFS file system, however my ZFS systems recent failure has made me look at the entire way I utilise storage for my photography business.
I should state from the out set that no important data was lost. I have backups and I was “lucky”, however the hidden achilles heal with all systems is hardware failure. My ZFS system died as a 2TB drive was failing for weeks without giving any indication and it slowly but surely destroyed the file system beyond recovery as there were no errors until a day before its terminal failure. It was a great low powered system running off a 1GB USB drive. Next time I will likely use BSD Unix but that is for another post.
I will likely refer to ZFS off and on in the rest of this post.
DROBO REVIEW
Ease of Setup: Dead simple. Attach via USB or firewire cable and turn on. Install the Drobo software and format for your OS. Mac and PC both supported.
Expansion: Expandable to 16TB As simple as inserting additional drives, or replacing with larger ones as prompted.
Ease of Sharing: You can plug into a switch with USB connector builtin for this, or from your OS you can share. However there are NO permission levels so everyone has access to everything, and can delete and overwrite as they please.
Front panel: Simple. Most info such as Drive status and storage used is easy to see. However you cannot tell if data is actually being written or read while the front panel is on. The light showing this is easy to view once the panel is removed. This is very simple and takes a second. Yup very fast tool-less access.
On/Off Switch: Noticably absent. How do you turn it off? With the older software you had a software standby button. With the newer dashboard software it is noticably absent. The online help says you just pull out the cable(!) and it will turn off. It does but this is just a bit odd.
Noise: Both of my Drobos have fans that are noticeable when on if you are in a quiet environment. I don’t mind this as because I live in the tropics I have a table fan running next to me most of the time I am sitting at the computer which effectively drowns them out.
Speed: Whether you use the the Firewire or USB versions of the Drobo you are stuck with a bit of a slug. It is NOT suited to for real time loading of large Lightroom or Bridge catalogues. Then again, running a catalogue from a server on 1GB ethernet from the ZFS server doesn’t really work that well for me either. Its best to do your editing on your primary machine.
Concatenation of Drives: The Drobo will alow you to join several smaller drives into what looks like one larger drive to your OS. We all have lots of older smaller drives around, so this is an excellent method of using them. e.g. say you have a old 250GB drive, a 300GB drive, and two 500GB drives. Using them all in a Drobo 4 bay unit will give you a consolidated drive that looks like a single 1.4TB drive. When one of those drives fails from old age, let’s say the oldest 250GB does, you replace it without losing data with another 5ooGB one you may have pulled from another old computer. Your capacity of “protected” data is now 1.63TB. I use “protected” in inverted commas as if the OS or the actual hardware fails you may well lose everything on the unit.
Rebuilding Drives: The easy to follow lights on the front of the unit let you know when you need to add another drive. Orange means add another drive and it is best to do so. The light will indicate the smallest drive which is the one to replace. A red light means the unit is nearly full. When the red light is on add new files at your PERIL as you are at real risk of locking the unit up and losing everything. A blinking red means one of the drives has failed. Your data is still safe but replacing the drive is pretty much a top priority as if another dies it is sayonara to EVERYTHING on the unit. Removing a drive is simple. Flick a lever and hopefully the drive will spring out. My units are old so leveraging with a chopstick is sometimes necessary. Like all RAIDs rebuilds can go for DAYS. Your Drobo Dashboard software widget will give you an idea on how long it will take. The bigger your drives the longer it takes. AFAIK the amount of data doesn’t matter as it is replicating and moving blocks over the full drive. It is best practice NOT to turn off your Drobos power however I found that turning off the connected computer or pulling out the USB or Firewire connector does not turn the Drobo off if in rebuild mode. Oh yes…your data is accessable during the rebuild but slower to access. If you use this method to save on your power bills you should be fine. The unit will go to sleep once the rebuild has finished. My longest rebuild so far has been over 90 hours.
Accidental power loss during rebuilds: Due to a couple of power outages and a cleaning lady, I have had power loss to the actual Drobo unit during rebuilds. Pretty scary however the unit has come back up and continued the rebuild once power was restored. I have UPS units connected now, however when I got my first Drobo these were still pretty clunky and very expensive. Fortunately they have become a lot more mainstream these days.
Drobo FAILURE: Yes, it has happened to me. Bad news when it does.
- The first time was when I selected slightly too many files to copy to the unit and went to bed. Remember copying a lot of data takes a long time. I woke up the next morning realising my calculations were off as the copy had stalled with about 5MB to go, however the Drobo was completely full and locked up. Rebooting did not fix the issue and neither did adding a larger drive. I had hosed the OS. Lesson: ALWAYS replace a drive when the lights show orange, which is when you have about 10% storage left. You can press on a little further but if you get the red light stop copying files onto it IMMEDIATELY. You are standing next to the cliff of chaos. Data chaos and corruption that is.
- The second time was during a firmware upgrade that went wrong. Everything gone. For good.
- There are no disc tools other than fdisk available for the Drobo. Fdisk is useful ONLY on NTFS and FAT32 formated drives but is pretty basic and totally useless for recovery.
Comparing the DROBO to FreeNas with ZFS:
- Freenas’ ZFS file system is very superior to hfs, NTFS, and Fat32 but if you have a hardware failure you run a risk of losing everything in your array. This is also true of the Drobo and one of the reasons I bought 2 of them as support from the USA to here is pretty limited.
- Setup with ZFS requires a fair amount of planning and some tinkering to get the shares working with different file systems. DROBO’s set up is insanely simple.
- Expansion wise the DROBO is extremely simple to expand up to 16GB. No thinking is required. ZFS requires a lot more forethought and planning when replacing, rebuilding and expanding drive pools. It also requires using the linux terminal prompt. Intimidating for most people.
- Speed: The Gigabit Ethernet with Freenas is NOTICEABLY faster than the Drobo on FW 800 or USB. I did not run file tests. No need to do this as it is obvious in real world scenarios. However it is still best to access files on your local computer than across a network.
- Recovery: Neither system is great. Drobo has no other tools other than fdisk which you can only run on NTFS and Fat32 volumes. No other tools are available. (Do not run fdisk on an HFS volume!) ZFS requires a working knowlege of Unix/Linux. In some situations like hardware failure you are in trouble no matter what.
Best use of your Drobo: Drobos are PERFECT replacements for older backup storage media like TAPE drives. If you use Apples Time Machine you will be very happy with the unit. If you are using Windows you can use Drobos own (limited) back up software built into the latest Drobo Dashboard, or SyncBack from 2brightsparks.com. I have used Microsofts Synctoy before but it can take a very long time and is not so good with reporting failures in synchronising, or on how to resolve issues.
As a photographer a second option is to use it to deposit your RAW files. My work flow is such that I copy directly from camera to a hard drive, and then copy from there to my working drive. Please note, it is a separate drive, NOT a partition on the same drive. This way I always have a back up in case of hard drive failure. The Drobo is quite useful for this.
Last of all, if you have ripped your Digital media then it is excellent for attaching to your Media Centre Storage. Just make sure you have your files somewhere else for when it has problems.
Dangerous For: Frontline storage. Keeping only one copy of anything important on a Drobo is irresponsible. Don’t do it. Once it goes down you are likely going to lose everything with no chance of recovery. It is NOT a frontline storage system. I cannot stress this enough. When it works it will lull you into complacency. When it eventually lets you down and fails the pain will be mighty.
