How-To: One iTunes Library With Multiple Computers

By Jenny Kortina Oct. 13, 2008, 8:30am PT 95 Comments

I recently set up a Mac mini in my living room to act as a media server. Instead of trying to update separate music libraries every time I added songs to my collection, I was just adding the music to the Mac mini’s iTunes library and streaming it my laptop. That worked fine until I tried to sync my iPhone. For obvious (copyright) reasons you cannot sync an iPhone to a shared library.

I wanted access to my music on both machines, but I did not want to share my Macbook Air’s library because the laptop would have to be on with iTunes running for the Mac mini to have the music. At this point, I had to choose between running separate libraries and updating them independently or figure out a way to run one library that updated whenever I added music from either machine. I chose the latter of the two options.

Some advantages of having one iTunes library:

  • You can sync iPhones to any computer on the network
  • You can add and edit playlists on any computer on the network
  • You can add music on any computer on the network

Some things you should know before you begin:

  • If you are using a laptop and want to take all of your music with you, this is not the method for you. All of the music is stored on a networked drive, so it is only accessible when on the network. (You could set it up so your music can be streamed over the internet, but this article will not go over that).
  • You can only make updates to one music library at a time — you cannot have iTunes open on both computers and make changes. Make changes on one, then open the other one.
  • You need to close iTunes on the computer you made changes on, and reopen it on all other computers to see changes

Those are all of the limitations I have found, so if those do not bother you, read on!

The Setup

The Mac mini runs Plex for watching movies, iTunes for managing my music, and is connected to the internet so we can watch our online video content (Hulu, South Park Studios and Snackfeed being my favorites). All of my movies and music are stored on a NAS that each computer on the network has access to.

A: Mapping iTunes Music Folders

The first thing we need to do is point each computer’s iTunes music folder to the same location. There are two different methods for this. If you have an NAS (Networked storage drive) follow procedure 1, if you are going to use one computer as the host (a server or tower that’s always on) follow procedure 2.

Procedure 1:

  1. iTunes > Preferences
  2. Go to the “Advanced” tab
  3. Click the “General” tab
  4. Under the “iTunes Music Folder Location” click the “Change” button
  5. Navigate to your NAS and create a folder called “Music”
  6. Click “Open”
  7. Click “OK” — you should now be back at a normal iTunes window
  8. Complete this on each computer. So in my case I did this with the Mac mini and the Macbook Air. When you have completed this procedure on each computer, move on to the next step – “B: Universal Library Setup”

Procedure 2:
Go to the computer that’s going to act as the music host (the one that will be sharing your music to all of your other computers). We are going to leave the iTunes music folder in the default location on this computer, but share it on the network so all of the other computers can see it.

  1. Go to Applications > System Preferences
  2. Click “Sharing” under the “Internet & Networking” section
  3. Click the check box next to “File Sharing”
  4. Under the “Shared Folders” section, click the plus arrow

  5. Navigate to your iTunes Music folder: HD > Users > Your Username > Music > iTunes > iTunes Music
  6. Click “Add”
  7. Close System Preferences. You’re done on this computer for now.
  8. Now go to a computer that is going to be streaming music from this one and continue to procedure directly below.

To stream music from the host computer to other computers:

  1. Go to a client machine.
  2. Open iTunes > Preferences
  3. Go to the “Advanced” tab
  4. Click the “General” tab
  5. Under the “iTunes Music Folder Location” click the “Change” button
  6. Navigate to the iTunes music folder we just shared from the host computer
  7. Click “Open”
  8. Click “OK” — you should now be back at a normal iTunes window
  9. Complete this on each computer. So in my case I did this with the Mac mini and the Macbook Air. When you have completed this procedure on each computer, move on to the next step –”Universal Library Setup”

At this point, all of your computers are accessing the same music library. Now all we have to do is make sure all the computers are accessing the same master index. Onward, to the universal library setup!

B: Universal Library Setup

At this point, both computers are accessing music from the same folder. Now we are going to make them access the same index file and album artwork. Once again, there are two different methods for this. If you have an NAS (Networked storage drive) follow procedure 1, if you are going to use one computer as the host (a server or tower that’s always on) follow procedure 2.

Procedure 1:

  1. Now we are ready to point our iTunes index to our LAN. While holding option, double click on your iTunes icon.
  2. A “Choose your library” window will pop up. Select “Create Library.”
  3. A window will pop up. Under “Where” select your a location on your NAS from the pulldown. Save as: “iTunes1″. iTunes will Launch. Close it.
  4. We’re done on this computer.
  5. Now go to a client computer and continue to “The client machine” below

Procedure 2:
Go to the computer that’s going to act as the music host (the one that will be sharing your music to all of your other computers). We are going to leave the iTunes index XML file in the default location on this computer, but share it on the network so all of the other computers can see it.

  1. Go to Applications > System Preferences
  2. Click “Sharing” under the “Internet & Networking” section
  3. Click the check box next to “File Sharing”
  4. Under the “Shared Folders” section, click the plus arrow
  5. Navigate to your iTunes folder where the XML file is stored: HD > Users > Your Username > Music > iTunes
  6. Click “Add”
  7. Close System Preferences. You’re done on this computer for now.
  8. Now go to a computer that is going to be streaming music from this one and continue to the procedure directly below.

The client machine:

  1. We are ready to point our iTunes to the shared index. While holding option, double click on your iTunes icon.
  2. A “Choose your library” window will pop up. Select “Choose Library.”
  3. A window will pop up. Navigate to the iTunes index XML file just set up on the NAS or shared from our host computer. You should see a folder called “iTunes1″. Open it.
  4. iTunes will Launch. Close it. We’re done on this computer. Repeat this procedure on all other client machines.

You’re now ready to roll. Simply add music to any computer you want, making sure iTunes is closed on all other computers, then when you are done adding your tunes, close iTunes and wait for Dropbox to upload your files. Once Dropbox is done uploading your updated library XML files, fire up iTunes on another computer and you will see your freshly added tunes. Enjoy!

NOTE: All the software mentioned is cross platform, so this method will work on your Windows machines as well!

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