How To: keep your iTunes library on an external hard drive

After discu ing how my iTunes library is set up with a few readers in the comments on my First Impre io /2G iPod nano post, I figured this might be a handy tip for readers who find themselves ru ing out of room to store an expanding iTunes library. My only machine is a MacBook Pro with a 120GB hard drive, but after i talling ~ 40GB of the entire Final Cut Studio suite and other various software and projects, I don't have room for my ~ 35GB iTunes library.

I decided to do some experimenting a couple weeks back with moving and keeping my library on an external hard drive. There are obvious initial disadvantages to this, but after some tinkering and getting comfortable with iTunes' baked-in library management genius, this can be a pretty useful setup for those who, like me, are cramped for ace but aren't willing to trash those albums you're too embarra ed use in a Party Shuffle playlist. This setup also has the inherent, and obvious, advantage of keeping your library on an external hard drive, so it's more or le already backed up - though I, with my paranoid data habits, keep a backup of my library on a second hard drive, and I now also use Scott's iTunes 7 backup tip (i tead of a previous Smart Playlist system) to burn my library to DVDs (the le on from someone who knows: your data can never be too backed up - ever).

Getting back on topic: read on for a walkthrough (from a very mobile notebook user) of how to move your iTunes library to an external hard drive. I'll include some ti on how iTunes is already one step ahead of this setup, as well as a few habits you might need to adopt when living la vida external-iTunes-library.

< an style="font-weight: bold;">The Setup
This i 't very difficult, but for those who aren't familiar with looking under iTunes' hood, I figured I'd lay this out and start from square one to make sure everyone can play along.
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The one initial catch with ru ing your iTunes library from an external drive is that you'll need a FireWire or U 2 drive for best performance; I have no idea how well this setup would perform on older machines with U 1, or if it would even work at all.

Now, if you're like most iTunes users, your library of music and movies (and now games) is stored locally on your Mac in ~/Music/iTunes/ (where ~ is your Home folder). With the latest iTunes 7 update, there are now (typically) two folders and two files in here (pictured above):

• Album Artwork folder (new with iTunes 7; mi ing from iTunes 6 and previous versio )
• iTunes Library (a database file iTunes needs)
• iTunes Music folder (this is where all your actual media like songs, podcasts, movies, and games live)
• iTunes Music Library (an XML library file iTunes also needs)

Now I'm sure that, as with many tricks like this, there are a number of ways to accomplish the task. I'm simply going to lay out the easiest and most ha le-free method I know of, as it worked mighty fine for me, and there are really only two ste :

1. if iTunes is ru ing, quit it
2. The only part of your iTunes folder you actually should move to the external hard drive is the iTunes Music folder (the one that holds all your media) itself; leave the Album Arwork folder, as well as the iTunes Library and iTunes Music Library files in place, locally on your Mac. Of course, if you want to < an style="font-style: italic;">back up your iTunes library for safe keeping (which I highly recommend, and again: Scott's iTunes 7 backup walkthrough is a great way to do it), including all your metadata, song ratings, song comments, etc., you should back up these local files in addition to your media

That's it - you've moved your library - you just need to let iTunes know where you moved all its stuff.


< an style="font-weight: bold;">The Configuration
Fortunately, telling iTunes where its library now lives is a one-step proce .

< an style="font-weight: bold;"> Go into iTunes' Preferences > Advanced pane, and click on the General tab. At the top of this tab is a record of where your library - your actual media - resides and, as you might gue , you can click the 'Change...' button to tell iTunes it's ho ed the pond to external hard drive pastures. You simply need to browse through the Finder dialog and select your media library, wherever you put it, and click OK. That's it - iTunes writes the nece ary changes to those aforementioned local database and XML library files, and you don't have to do any more heavy lifting. As long as your drive is still mounted and ru ing, you can start playing your media just like before.

Unfortunately though, now that you're enjoying external iTunes library bli , it's time to burst your bu le with a few gotchas to look out for. It's certainly po ible to keep on trucking with this kind of setup (otherwise this would be a pretty usele post), but there are definitely some co traints to co ider when going down this road.


< an style="font-weight: bold;">The Gotchas
The most significant catch is, of course, the fact that if you ever disco ect your drive - perha you're a mobile notebook user like myself - you obviously can't play any of your media in iTunes. Unle you own an iPod and enable the setting to manage its music yourself, you're pretty much out of luck here.

As you might expect, this also mea that managing an iPod with this setup can get quirky too. If you sync your iPod with iTunes, and you co ect it while your library is u lugged, iTunes will freak out and, after a few moments, warn you that it can't update your iPod because none of your media is present. However: this doe 't remove any music from your iPod, and your iTunes media will be playable once you co ect your drive again. A lot of those 'file not found' exclamation points will a ear next to your songs in the iTunes media list after a scenario like this, but don't panic: once you reco ect your drive (and/or restart iTune that one's up to you), all your media will play and sync just fine again. I've tested this with both a 5G iPod and a nano.

If you want to be able to plug in your iPod and exchange files and folders without iTunes automatically starting (and potentially bringing up the aforementioned quirks), uncheck the 'start iTunes automatically when this iPod is co ected' option. This way iTunes only starts when you're good and ready to interact with your media and/or your iPod. These might not be easy habits to develop if you're used to iTunes ru ing the show for you, but they're most likely nece ary if you've read this far into the post and you're still interested in living the external library lifestyle.


< an style="font-weight: bold;">But what ha e if I import media, download podcasts or buy something from the iTunes Store?
This is one of the many areas where I must tip my hat to A le's engineers, for they really knocked one out of the park when it comes to this situation.
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Ever wonder what the Advanced > Co olidate Library menu option does? Well, it was made for just such a setup as your new external iTunes library. If your drive i 't co ected when you start iTunes and, for example, import a CD or download a su cribed podcast, iTunes needs to put it somewhere, and it defaults to placing that media in your local ~/Music/iTunes/iTunes Music/ folder. "But TUAW, this is going to turn my library into a me !" you exclaim from atop your desk chair. Fear not, intrepid reader, for the Advanced > Co olidate Library command is to the rescue! This ingenious command tells iTunes to copy any media it's imported to the local default media folder over to your recently customized external folder - once it's reco ected, of course. This is beautiful, because it's a two-click proce to move all that new media over with the rest of your library and organize it properly, defusing a potentially complicated library me .

However, a fortunate perk of iTunes' ability to have a lit library personality is its ability to update an iPod with a new podcast or recently imported album while you're out 'n about, sa -external library drive. This has the potential to get confusing though, so for the sake of your organizational sanity, I hope you don't need your new podcast episode fix too often while you're on the go.

Finally, as far as reuniting your libraries is concerned, it seems that iTunes < an style="font-style: italic;">copies your new media files over to the drive when co olidating, i tead of < an style="font-style: italic;">moving them. Every so often after you run this option, it might be a good idea to dig into your local iTunes Music folder and trash all those files, as they're just dead weight after a co olidation.


< an style="font-weight: bold;">Be one with your external iTunes Library, young Padawan
This should be just about everything you need to cut the chord on your iTunes library if you're looking to save ace on your Mac, or if you're simply a nut for using external hard drives. I've been poking around at this setup for about a month now, and I've been pretty ha y with it. Aside from the catches I mentioned to watch out for, I was able to save almost 35GB of ace on my MacBook Pro and make way for other projects, with room to are. As always with feature posts like this, I'll try to a wer any questio you may have in the comments. Enjoy!
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