Q: What is a “volume”?

A: The term volume is used to refer to a pool of storage that Drobo makes available to the operating system. With firmware release 1.1.1 Drobo allows users the ability to choose different volume sizes.

Q: What is the “large volume” feature?

A: With firmware 1.1.1 Drobo can support various volume sizes based on the file system format you use and the operating system it is connected to as shown below:

HFS+	NTFS	EXT3 (in beta)	FAT32
1,2,4,8,or 16 TB	XP: 2 TB Vista: 1,2,4,8,or 16  TB	1, 2 TB	1, 2 TB

 

Q: What happens if my total storage is larger than the volume size?

A: If the protected storage from the drives put into Drobo is larger than the volume size, then Drobo automatically creates a second volume of the same size. If more than 2 TB of protected space were available, say for the case where it has four 1TB hard drives, then Drobo would present itself as two, 2TB disks to the operating system.

Q: What does it take to increase Drobo to a 16TB volume from an existing volume of a different size?

A: Increasing your current volume to a larger one requires a reformat where all data will be erased (hence you must migrate it to a different location beforehand). This is a limitation of existing file systems. Unfortunately, they do not allow on-the-fly upsizing. It’s analogous to increasing the size of your house by a factor of eight (8). You have to demolish the house, rebuild the foundation, and then rebuild the house. Of course, you will have to move your possessions in and out if you want to keep them.

In this example, increasing Drobo’s volume size corresponds to increasing the square footage of the foundation eightfold. Next you have to rebuild the file system – or the house in this analogy. Your possessions correspond to the data stored on Drobo.

Q: Should I increase my Drobo to be a 16TB volume?

A: There is no technical reason to do so. You may like the convenience of having one, very large volume where your data is stored. This can eliminate the mental overhead of finding where you put something. “In which drive (D:\, E:\, F:\,…) or disk volume (Drobo1, Drobo2, ….) did I store that important document?” Increasing the volume size will take time (procedure described below) and you will have to weigh the benefits for yourself.

Q: Will making Drobo 4, 8 , or 16 TB affect boot time?

A: The larger volume size you choose for Drobo, the longer Drobo will take to boot. This is because at boot up your computer scans disks to ensure they ready for use. A 16 TB Drobo is significantly larger than, for example, a 125GB drive in a notebooks, or even a 1 TB drive in a desk-side PC.

Q: Will making Drobo 4, 8, or 16 TB affect anything else?

A: Your computer will write its “file system meta data” onto Drobo. This is information it uses to store and access data on Drobo. Larger volume sizes require larger amounts of meta data. Hence, there will be more space that is reserved for a 16TB volume before it is actually used than a 2TB volume.

Q: Are there any risks with making Drobo 4, 8, or 16 TB?

A: No. Please note though that if you are migrating data off of Drobo onto other disk drives or using file sharing on other computers then your data could be at risk–depending on the reliability of those other devices. The safest thing to do is to copy your data onto another Drobo, then reformat your original Drobo, and then copy the data back.

Q: What happens if I don’t format Drobo to be larger than TB?

A: As you add larger disk drives, Drobo will present additional 2 TB volumes to your computer. You will see another drive letter (Windows) or volume name (OS X) on your computer.

Q: I really want to make my Drobo 4, 8, or 16 TBs. How do I do it?

A: Please be aware this can take several days from start to finish depending on how much data is on your Drobo. The steps are as follows:

1. Make sure you update your Drobo and Drobo Dashboard to the 1.1.1 firmware release.
2. Copy data off of Drobo onto other disk drives and/or computers to hold it.
3. Double check to ensure you’ve copied all data off of your Drobo successfully!
4. Use Drobo Dashboard to reformat your Drobo to the volume size you want.
5. Copy data from those other disk drives and/or computers back on to Drobo.

Q: Can I use Drobo as a backup target for Time Machine?

A: Yes. The two are a perfect combination. Time Machine requires an external drive such as Drobo to work. Drobo protects you from hard drive failure; Time Machine protects you from accidentally changing or deleting files.

Q: How can I use Time Machine and Drobo to do network backups?

A: Time Machine can do network backups to another Mac. The new Finder in OS X 10.5 makes sharing drives easy. Plug Drobo into a Mac on the network and setup your system preferences to share the Drobo. Set Time Machine’s Preferences on Macs in the network to use the Drobo on the Mac acting as a network resource.

Q: Can I connect Drobo to a Time Capsule or Airport Extreme Base Station and have it work with Time Machine?

A: Yes, just make sure you have updated Time Capsule or Airport Extreme to firmware 7.3.1 or later.

Q: Can I use DroboShare + Drobo as a backup target for Time Machine?

A: No. At this time Time Machine does not support network backup to devices using the cross-platform SMB network storage protocol that DroboShare utilizes.

Q: Why do I read blogs or forum posts about using Time Machine and SMB NAS devices?

A: Advanced users in the Apple community have found ways to trick Time Machine into working with SMB storage. However Apple does not support this functionality. We have heard from knowledgeable developers that data corruption can occur if the size of the backup exceeds 2TB or if a large number of files, on the order of a million, are backed up. Because the exact conditions leading to data corruption are not well quantified DRI recommends not experimenting with this unsupported capability.

Q: Why would I use Drobo with Apple’s Time Capsule or Airport Extreme?

A: Drobo compliments Time Capsule and provides three additional benefits:

• Capacity: Time Capsule and Airport Extreme are limited to 1 TB maximum capacity. With Drobo, you can get 2 TB for use by Time Machine, twice as big as the alternatives.
• Expandability: you can add capacity to Drobo by adding drives, or replacing smaller drives with larger ones.
• Redundancy: : Drobo uses multiple drives which protects your data against a single drive failure. Time Capsule is a single drive system.

	Time Capsule	Airport Extreme	Drobo and Time Capsule or Airport Extreme	Drobo connected to a Mac
Time Machine maximum data size	1 TB	Depends on size of external drive up to 2 TB maximum	2 TB	16 TB
Protection from hard drive failure	No	Yes – if Drobo connected	Yes	Yes
Expandable	No	Yes – if Drobo connected	Yes	Yes

Q: Why is capacity limited to 2 TB if I use Drobo with Time Capsule or Airport Extreme?

A: This is a restriction in Apple’s Time Capsule and Airport Express products. If you need more capacity, then you can connect Drobo directly to a Mac.

Q: What is the largest capacity Drobo I can create today?

A: At the time of this writing, March 2008, 1 TB drives are the largest available on the market. Plugging four of these into Drobo results in 3 TB of protected space available for Time Machine. As larger disk drives become available you can increase Drobo’s capacity by replacing its drives with larger ones. Drobo can support a single volume of up to 16TB.

Q: Is there a difference in how Time Machine works when Drobo is connected directly to a Mac versus connected directly to a Mac that is shared over a network?

A: If Drobo is plugged directly into a Mac then Time Machine makes a copy of the files that it backs up. Using Finder you can directly browse them. If Time Machine makes backups over a network to a Drobo connected to a Time Capsule, Airport Extreme, or another Mac, then the backups are created as a “sparse bundle” that must first be mounted before it can be browsed (first select the bundle and do an Apple-O key combination you will then see a disk icon appear on your desktop, you can then select that icon and browse it with Finder).

Q: How do I format Drobo for use with Time Capsule or Airport Express?

A: You can use the Drobo Dashboard to do the formatting -- its default settings work with Time Capsule and Airport Express. These defaults are: single partition, 2 TB volume with an HFS+ journaled file system. If you want to configure it manually, then use OS X’s DiskUtility and make sure the volume is 2 TB or smaller, and you select an HFS+ journaled file system.

Q: I though Airport Extreme didn’t work with journaled file systems.

A: With firmware 7.3.1 the Airport Extreme works with journaled file systems. When it first shipped, in 2/2007, non-journaled file systems were required for disks greater than 1 TB in size.

Q: How can I limit how much space Time Machine uses on my Drobo?

A: To limit how much space Time Machine uses you will need to create a partition on Drobo for use by Time Machine. You will need to use OS X’s DiskUtility in order to do this. Note that you can not create a partition on a Drobo that has data on it without OS X erasing all that data

Q: What does Time Machine do as Drobo gets full?

A: If Time Machine is not running in a dedicated partition, then it will grow to consume all of the available capacity in Drobo. As Drobo gets full it will enter “yellow mode” and it will prompt you to add storage. When this happens, the data bay indicator next to the smallest capacity drive will turn yellow on Drobo, Drobo Dashboard will turn yellow and you will receive an email alert if you are using that feature. If you do nothing and Time Machine keeps adding data then at 95% full Drobo will enter “red mode”. When this occurs, the data bay indicator next to the smallest capacity drive will turn red on Drobo, Drobo Dashboard will turn red and you will receive an email alert if you are using that feature. In red mode, Drobo will start to slow down as yet another reminder to you that it’s low on space.

Q: What is the worst thing that can happen if I run Time Machine and Drobo gets full?

A: All data that has been backed up on Drobo is safe. If you ignore Drobo’s warnings and just let Time Machine write to Drobo, the worst thing that will happen is that Time Machine will get slower and slower.

Q: Can I use Drobo Dashboard if Drobo is connected to a Time Capsule or Airport Extreme?

A: No. Drobo Dashboard communicates with Drobo over its USB connection. When Drobo is plugged into Time Capsule or Airport Extreme there is no way to communicate to its USB port. In this case, look at Drobo’s data bay indicator lights to check its status.

Q: I started using Time Machine on a non-Drobo drive and it’s out of space. What can I do?

A: Drobo and SuperDuper! (a 3^rd party backup program) will help you out. Using SuperDuper! you can make an exact clone of that smaller drive that has your Time Machine data onto Drobo. This will give you more room for your Time Machine backups. Be aware that using the free version of SuperDuper! will erase the data on your Drobo before making a clone of your small drive. If this isn’t what you want, then you better buy the registered version. Using either its “Copy newer” or “Copy different” options will copy to your Drobo without erasing it.

How Do I Backup My Drobo?

Are you asking “How should I back up my Drobo?” or “How can I back up Drobo to an offsite system?” or “How should I back up my computer(s) to Drobo”? This note is first of a series that will investigate these questions.

This note will present tools for Mac or Windows users to backup your Drobo so that your data is protected against fire, flood, theft, or other damage.

How to backup Drobo?

Eighty-five percent (85%) of Drobo owners use it to backup other systems, and as primary storage (i.e. only location) for other valuable data. While Drobo is designed to protect against single drive failure, many are looking for additional protection against fire, flood, theft, or other calamities that can damage their system, Drobo, and data.

The mean amount of data Drobo owners have is 2.6TB. To back up that much data, the optimal solution is another Drobo plus automatic backup software. What does “optimal” mean? It means that backup is handled automatically, that the user doesn’t have to try to partition and backup subsets of the data to multiple devices, and that the user can backup to either another Drobo, or one that is shared on a network.

What free or low cost backup software can I use?

There are many different types of backup software. They are differentiated by the types of backup operations they perform (one way or two way sync, incremental, etc.),  price, and how much user configuration is required. Our preference is for something that is straight forward to setup and use, and low cost.

Data Robotics has tested, certifies, and recommends the packages shown below:

With these packages you can easily backup one Drobo to another. Please note that unless you move and store one Drobo to a different location, they are both exposed to fire or other risk factors. You can re-sync your Drobos by periodically connecting them both to the same computer and re-running the backup software.

Why are these packages recommended?

Both of these packages have the following features in common:

• Backup copy is readable by the computer’s OS, i.e. it’s not a proprietary format.
• Simple set up – all the user needs to do is specify a “copy from” and “copy to” locations.
• Backup targets can be either another directly attached Drobo, or a Drobo connected to a DroboShare or another computer.
• Choice of a one-time copy or scheduled recurring backups.
• Cost – free versions are fully functional.