One of Drobo's chief value-adds is that it's easy to set up and use. It's made for people who don't want to make a career or hobby out of storage mangement. The quick start card that you can't miss as you unpack your Drobo points you to a setup wizard at http://www.drobo.com/start that walks you through everything you need to do. It even has a fork to handle migrating a set of drives from another Drobo. The 5N video below provides a good overview of the setup process.
There is no web admin interface in the 5N2. Instead, you install Windows or MacOS Drobo Dashboard apps to manage one or many Drobos. The default view shows all Drobos detected, both direct and network attached flavors.
Drobo Dash - All Drobos
Double clicking on a Drobo brings up its Status. You can cycle through System, Drive and Network status screens.
Drobo Dash - Status
Drobo's "Beyond RAID" system is the grand-daddy (or mother) of the hybrid / automatic RAID systems. Key differences from other automatic RAID systems are the ability to mix drive sizes and to change drive sizes as your capacity requirements grow. Although you can do that on other NASes, volume size will be limited by the smallest drive. With Beyond RAID, you'll get more total capacity.
For example, Drobo's Capacity Calculator shows three 1 TB drives will yield a 1.81 TB volume and three 2 TB drives will yield 3.63 TB. Changing one of the three 2 TB drives to 1 TB drops capacity down to only 2.72 TB instead of 1.81. Note that each drive swap will initiate a volume rebuild process that will take hours.
As with any other RAID system, if something happens during that rebuild process, you can lose your volume, unless you enable dual-disk redundancy. Still, you need to be as careful with Drobo as you are with any other centralized data storage device. This means putting it on a UPS / battery backup and not trusting it to be the sole repository of your precious data.
The Capacity screen shows the capacity of the single volume created from all inserted drives. The 5N2 supports a single volume up to 64 TB. The 1.64 TB capacity shown here results from four 1 TB drives with dual-disk redundancy enabled. The default configuration allows one drive to fail without killing the volume.
Drobo Dash - Capacity
Shares can be created, assigned to users and have access privileges set. A mapped drive is automatically created in Windows for each share if you're running Drobo Dashboard. If you're not, you can still browse to shares and create your own drive mapping if you desire. SMB and AFP network file systems are supported by default.
Drobo Dash - Shares
You have the option of assigning a share to MacOS Time Machine backup. The space you assign when creating this share is reserved exclusively for Time Machine backup in that space isn't reclaimed as data is deleted.
Drobo has a decent set of installable apps that are managed via the Drobo Apps page.
Drobo Dash - Apps
The list includes the apps shown below. An up-to-date list is found here. Note that FTP support can be added by installing ProFTPD and NFS via an NFS app. Linux shell access can be added by installing the Bash shell and Dropbear SSH apps.
Drobo App list
Drobo's most glaring weakness is in backing up its own data. The 5N2 has no USB ports, so attached backup is out. The main local backup solution is DroboDR, a replication feature that requires another Drobo as target. DroboDR incrementally backs up the entire Drobo volume to a target NAS on a scheduled basis, with two hours as the smallest interval. Versioning and snapshotting are not supported.
Drobo DR setup
The only other options for backing up the 5N2 are BitTorrent Sync, ElephantDrive, ownCloud and Pydio cloud services. Each is supported via an installable app.
Remote access to your files is enabled via the myDrobo app. DroboPix and companion iOS and Android apps let you view and play photos, music and videos and DroboAccess does the same for web browser access.
One final feature worthy of note is Drobo's Network Interface Bonding for its two Gigabit Ethernet ports. Drobo says this feature does not require 802.3ad link aggregation support on your network switch. Just connect both Drobo's ports to ports on your switch, check the Network Interface Bonding box on the Network Settings screen and restart. You'll get a new IP address for your bonded port and higher throughput when multiple devices are simultaneously accessing the Drobo.