# Room to Grow: Data Storage for Your Mac Explained

This post is part of a series called Data Backups and Storage.
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Thanks to the wide availability of high-speed broadband, the iTunes Store and Time Machine, we’re storing more data than ever before. Whilst it was only a few years ago that 80GB was more than adequate, nowadays we’re often struggling to find space to save all our data, especially in a household with multiple Macs.

In this tutorial, I’ll show you a selection of different storage solutions that are designed to work with the Mac as well as helping you decide on the best one for you.

## Need More Storage?

If you’re often finding your Mac displays a warning that says Your startup disk is almost full or you’re constantly having to delete old files to make way for new ones, then you’re in need of some additional storage. More storage space means you can spend less time constantly battling the finite amount of space within your Mac.

Apple’s desktop Macs, as well as it’s ageing MacBook Pro product line, use traditional mechanical hard drives which offer hundreds of gigabytes of storage, leaving you plenty of room to grow an iTunes or iPhoto library before you ever need to look at getting more space.

SSDs (solid state drives) offer much faster speeds and reliability compared to mechanical drives. But as is always the case with hot new technologies, it comes at a price - it costs more per gigabyte than a mechanical hard drive.

If we compare the MacBook Pro range, Retina and non-Retina, we can see that the non-Retina models offer a minimum 500GB hard drive. The Retina models offer a minimum 128GB SSD option which is less than half the capacity. What’s more, upgrading the SSD to a larger size is still very expensive. What this means for owners of SSD-based Macs is that we’re often having to either reduce the amount of data we have or look towards additional storage.

Apple’s desktop Macs as well as it’s ageing MacBook Pro product line use traditional mechanical hard drives...

On average, the largest amounts of data on our Macs will likely be iTunes and iPhoto libraries. We’ve covered moving these libraries to an external hard drive previously on Mactuts+ with our tutorial “How to Move Your iTunes, iPhoto or Aperture Library to an External Drive”, as well as how to manage a full startup disk with “What To Do When Your Mac's Startup Disk is Full”.

Before moving your libraries, and any other large chunks of data, we need to find a good storage solution. Not all hard drives and storage solutions are created equal which means an external hard drive might not be the best option for some whilst a network storage device might not be the best option for others. Let’s take a look through the different solutions available for you to see which might best work with your situation.

## Local vs. Network

When it comes to storing files and folders, you can either store them on a hard drive attached to your Mac (local) or on a network storage device (Network). Both of these methods have their own advantages and disadvantages, depending on your requirements and circumstances.

### Local Storage

Local refers to something either physically connected to your Mac, so in the case of file storage we use this when we refer to any type of external hard drive. A local storage device isn’t just a hard drive though, there are some pretty advanced devices that push the boundaries of what a hard drive can do into some pretty incredible directions. This tends to be the perfect choice if you only need to be concerned with the space available on a single Mac.

The main advantages to local solutions is that they’re always going to be much faster than network storage devices, especially when working wirelessly. Even when using gigabit networking which can shuffle along data at 1Gbit/sec, USB 3.0 has a theoretical maximum of 5Gbit/sec. You’re also less likely to be using a gigabit network, instead more reliant upon either more traditional megabit speeds or wireless, which can often be the bottleneck in any network.

Another benefit of local storage is that there is usual no or only minimal setup required, just plug in your drive and away you go. Network storage requires more in-depth knowledge of setting up.

Some functionality or applications might only work with a local storage device, too. For example, Parallels can only run a virtual machine (such as an installation of Windows) from a local device - it can’t be used if the virtual machine’s files are stored on a network device.

### Network Storage

Network storage devices will sit on your home network and can be connected by either a network cable or, in some cases, wirelessly. These types of devices usually cost more than a local device such as an external hard drive as they operate independently of your Mac and are effectively a low-powered server.

The term NAS, Network Attached Storage, is something you’ll hear quite a lot and it essentially refers to a storage device, like a hard drive, that’s accessible over the network. In fact, that’s exactly what Apple’s AirPort Extreme (with a hard drive connected) or Time Capsule are.

Unlike network storage, a drawback to local storage is that they can only be really used with one Mac at a time. If you’ve got a couple of Macs at home that rely upon the same hard drive for backups, you’re constantly having to go to each Mac with the drive, perform the backup and then move on to the next. The same would apply if you have a drive full of photos, to view them on another Mac you’d have to move the drive and connect it.

A network storage solution would be centralised on your network and mean multiple Macs could be accessing and storing different data all at once. Many small businesses use NAS devices in lieu of a server now that many of the services that a server used to be beneficial for has been overshadowed by services such as hosted email.

Since a NAS will operate across your entire network, another benefit would be that all this is wireless so it’s one less cable to plug in to your Mac and you can be accessing data or making backups anywhere in the home.

Macs can work with many NAS devices since OS X supports Windows file sharing protocols such as CIFS as well as Apple’s file sharing protocol AFP, Apple Filing Protocol. This makes many of the ones on the market fully Mac compatible. Be cautious when deciding upon a NAS system though if you’re planning to use it for backing up, Time Machine can only back up to network devices that support AFP.

There are certain tradeoffs with network storage, one being that you can’t really take it with you. If you’re heading on a business trip and wanted to take your iTunes library, it’s easy to take along an external drive with you. But if you’ve placed your iTunes library on a network storage device then you’re not going to have that flexibility. As I mentioned at the start of this guide, each solution will have its own benefits and drawbacks.

## 1. Local

Let’s take a look at some examples of local storage solutions that you can use with your Mac.

Price: $70+ An external hard drive is the cheapest and easiest way of adding additional storage to your Mac. USB hard drives are by far the most popular type of external drive, offering the lowest cost overall. Almost all of Apple’s Mac range have USB 3.0 as standard which means you’re able to take advantage of it’s incredible speeds should you purchase a USB 3.0 compatible drive. There are even Thunderbolt-compatible drives as well as FireWire 800 drives if your Mac still supports it. Tip: Even if your Mac doesn’t support USB 3.0, there’s no reason not to buy a USB 3.0 drive. They’re fully backwards compatible and it means, should you ever purchase a newer Mac, you’ll then be able to take advantage of its amazing speed. If you’re just wanting to store movies, photos and music then any USB hard drive will your best choice. Their price and availability make them the perfect choice and if you’re able to use USB 3.0, the speeds really are incredible. Thunderbolt drives make a better option if you’re needing to constantly transfer large amounts of data to and from your Mac as quickly as possible (such as video editing). Even then, USB 3.0 still gives Thunderbolt a run for it’s money. ### Promise Pegasus RAID Price:$1,099+

Going from one end of the spectrum to the other, the Pegasus RAID is a behemoth of storage. Costing more than a Mac mini, it’s a Thunderbolt storage solution that’s not for the faint of heart and is aimed more towards server-grade storage rather than the home office.

There are two models depending on how much storage you want, the P4 and P6. The number denotes the number of drive bays it has available, all with a hard drive installed. Think of it as a huge external hard drive, rather than a collection of different drives, as that is actually how it operates.

Once up and running, this appears as a single drive on your Mac and actually works no different than an external drive, it’s just a place to store your data. Whilst this seems like quite a complex piece of equipment, it’s actually very simple to set up and use because they’re actually pre-configured out of the box.

What makes the Promise RAID special is given away in it’s name - RAID. This stands for Redundant Array of Inexpensive Disks. A common misconception is that a RAID solution is a backup, it’s actually not quite true.

RAID is a hugely complex subject which goes well beyond the scope of this guide but with regards to the Promise RAID, I’ll explain a little bit about it.

Tip: I’d recommend checking out the Wikipedia article on RAID for a full explanation of what RAID does.

The Promise RAID is configured, by default, as RAID–5. This means that some space on each drive is reserved for a feature known as Parity. If we had a Promise RAID that had 4 drive bays and 1TB drives in each, we’d actually have just under 3TB of actual space.

In the event that one of the drives fails, we actually won’t lose any data. Instead, the RAID system limps along using Parity as a way of rebuilding the data that the failed drive contained. This doesn’t mean we let the RAID stay that way, the failed drive needs to be replaced as soon as possible as one more drive failure means we lose everything.

RAID is more of a backup (or redundancy, hence the name) for hardware failure than data loss. If you deleted a file by accident then a RAID solution won’t bring it back. Where RAID excels is that hard drives can and do fail. If my Mac hard drive fails, I have a Time Machine backup. I can get the drive replaced and then restore from my backup and I won’t have lost any files. What I will have lost, however, is time. RAID is designed to provide a redundancy for this where that sort of downtime isn’t an option. When a drive fails, simply swap it out (it doesn’t even need to be powered off) and it will rebuild the data on the new drive.

Whilst its price might be out of reach for most home users, this device has found popularity in the small/medium business environment where a reliable, yet easy to maintain, storage solution is needed and can be found often attached to a Mac mini server providing file sharing for everyone in the office.

The Promise RAID was one of the first Thunderbolt devices to market and is used by many businesses the world over due to its ease of use and speeds it provides.

Price: $499+ Sitting somewhere in the middle of external hard drive and Promise RAID is the ever popular Drobo. It’s got more in common with the Promise RAID than an external hard drive but it has some clever trickery that makes this a great solution for those wanting a step up from an external hard drive, especially if they’re finding themselves continually buying new drives to replace full ones. The main draw towards the Drobo units is its extremely clever way of managing your drives. It works in a similar way to the Promise RAID, providing redundancy across all your drives in case of failure. But what sets it apart, however, is that you can mix and match any size and make of drive you have. It calls this feature BeyondRAID and it works very well indeed. The Drobo 5D, with USB 3.0 and Thunderbolt connectivity, has 5 empty drive bays for you to fill. Unlike a traditional RAID system where you need to ensure the same size (and usually make and model) of the drives, you can put in whatever size drives you want. If you’ve got a few older drives hanging around, let’s say a couple of 1TB drives and some 500GB drives, just put them all in. You don’t even need to fill all the bays in one go. Again, just like the Promise RAID, you won’t get all the space the drives add up to because there will be some space saved for parity. Drobo also displays all your space as just one drive, making it easy to manage all the space you could possibly need (there’s nothing worse than moving between hard drives, especially when one is full and the other is empty). What’s really neat about the Drobo is that once you’re running out of space, you can simply pull out the smallest drive and upgrade it with a new one which Drobo will configure automatically, all without powering it down. Once the new drive is set up, you’ll find the available storage will increase and you can keep doing this every time you start running out of space. The Drobo solutions are also a little pricey but they’re much cheaper than something like the Promise RAID. You don’t get any drives with a Drobo, either - that’s up to you to get separately. As you’re able to add any drive you want then you don’t have to worry about matching drives and sizes meaning you can buy what you can afford now and upgrade later. Just like the Promise RAID, they’re fully Mac compatible and include management software to keep your Drobo running as smoothly as possible. ## 2. Network ### AirPort Extreme / Time Capsule Price:$179+

Let’s start with Apple’s offerings. Both the AirPort Extreme and Time Capsule have a USB port that allows you to share a USB hard drive with everyone on the network (don’t worry, it can be password protected). This functionality turns your Airport Extreme or Time Capsule into a low-cost file server, letting multiple Macs on the same network access files and folders as well as perform Time Machine backups.

The Time Capsule itself also contains an internal 2TB or 3TB hard drive. You don’t have to the space just for backups, either. You can store anything you want on a Time Capsule and have it accessible over the network.

There are a few drawbacks to using Apple’s offerings as a way to store files. Whilst they’re perfect for backup storage, there’s no easy way to backup the files located on either the USB hard drive or Time Capsule’s drives. Anything you put on these would either have to be something you wouldn’t miss if it failed or be prepared to set up an extremely convoluted way of backing them up, which would likely negate their usefulness in the end.

Price: $199+ Synology is a name with which you might not be familiar but they’re a big name in the network storage sector. They offer a range of networked storage devices ranging from ones that can run off a single drive to huge twelve bay solutions. Unlike the AirPort range, Synology devices have a web interface for administration since each device runs Synology’s custom OS that’s based upon Linux. They support common file transfer protocols such as CIFS and Apple’s AFP, making them ideal in a Windows and Mac environment. Because of the advanced software that runs on Synology devices, they can do a lot more than just file storage. There’s a great plugin ecosystem that lets you customise your Synology to provide features such as web hosting, file downloads using BitTorrent and even a Dropbox client to have your Dropbox sync with it. As with the Drobo I mentioned earlier, Synology devices require hard drive to be purchased and fitted separately. Their larger devices support traditional RAID solutions as well as their own “Hybrid RAID”, similar to Drobo’s, where you can mix and match different size and types of drives. One particular feature that Synology has going for it is it’s built-in backup software to backup data that resides on it. Most of the mid to high-end Synology devices include a USB port, allowing for the attachment of a USB drive in the same way you can do so with the AirPort Extreme. What sets the Synology apart is that not only can you share files that are on the USB drive, you can schedule the Synology to backup to the USB drive as well. If you’re feeling particularly adventurous, Synology even offers the ability to backup to another Synology, meaning you could have a constantly running off-site backup to somewhere else. This backups feature addresses the biggest shortcoming with network storage in the home or small office: backing up data that’s on them. Setting up a Synology is really easy and the accompanying Synology Setup Manager for Mac allows you to easily find newly powered on Synology devices on the network to then log in and configure. Whilst they’re easy to use, they do require a degree of technical proficiency should you come across any problems or if you want to take advantage of some of the other features it can provide. ### Drobo… Again Price:$599+

We’ve already discussed Drobo before, but it’s worth mentioning that they also offer a network-based alternative that doesn’t require it to be plugged into a Mac. It offers the same features as the local version has but in a centralised solution, making it perfect for a multi-Mac environment.

Unlike the local storage solution, Drobo’s network device is connected to your network and accessible for multiple users to connect to. You get the same features as you would with the standard Drobo but without having to connect it to just one Mac.

## Which is Right For Me?

There’s a lot of information in this guide and there really isn’t a right or wrong solution, only one that best fits your needs. If you’re only looking to store additional files for a single Mac then an external hard drive might be the best fit.

If you’re often buying additional external drives or constantly replacing with newer, larger ones then a Drobo might be the complete solution you need.

For those with several Macs in the household then a NAS device would be the perfect fit for providing a centralised way of storing files as well as ensuring all Macs are regularly backing up.

If you do opt for a NAS solution, remember to make sure that any data you store on it that isn’t available elsewhere is backed up. Should that be the case, then the Synology range of devices might be what you’re looking for with their excellent support for backing up data that they’re storing.

## Wrapping Up

Whatever your requirements are for storing large amounts of data, there are plenty of options available. It’s always important to plan not only what your requirements are now but what you expect they’ll be in the not too distant future. Purchasing a 4TB Promise RAID would be an expensive mistake to make if you already have 3TB of data to store since it leaves you with no room to add additional files.

Above all else, the decision is ultimately yours to make and no-one can say whether it was the right or wrong one. Make sure you plan your storage needs properly and there’s no reason they can’t last you a long, long time.