How Do I Point iTunes to use my backup ext drive?


I use iTunes on a Mac Mini with 2 external 500GB disk drives. I use one of the external disk drives strictly as a backup. All I do to backup my iTunes information is I copy the complete contents of the iTUNES folder on my primary drive to the backup drive by the drag & drop (copy) feature. As you Mac users know, the iTunes folder contains 4 sub folders with the Music Library, Album artwork and XML file.

Well the dreaded day has come and I suffered a hard disk crash. No problem as my backup disk contains all of my needed iTunes files. However when I try to access my playlists, iTunes tells me it can't find the song title. I can change the location of the song title to the backup drive and it finds it successfully, but with over 4,000 songs ripped I can't imagine that I have to do this for every song. I changed the Advanced Preferences in iTunes to point to the backup location, but I think this is only to tell iTunes where to rip new music.

How do I tell iTunes to reference the backup drive so that it can find my playlists and music files?

Thanks in advance,
Brian ...
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Since Herman has thrown down the gauntlet, I'll try to shed some light on this whole iTunes thing--with the very clear disclaimer that I am not a computer scientist, programmer, or even, for that matter, a Unix jockey.

The whole "flogging" thing was, of course, directed towards the aforementioned dead horse, not any of our esteemed 'Gon'ers. So even though Herman has admitted to actually enjoying being flogged, perhaps this personal tidbit is best kept between him and his therapist(s). Or as the old joke goes:

Masochist: Go ahead, hit me!

Sadist: No way!

So let the flogging begin....

It seems one of the primary causes of confusion in these iTunes discussions is nomenclature. Apple is at least partly to blame for this by using terms that are often less than clear, or even downright ambiguous. The prime example is the term "iTunes Library."

This term is merely a concept that refers to the complete collection of software components and data used by iTunes to perform its familiar functions, such as playing music, displaying album art, keeping track of playlists, presenting track information, etc., etc. Your "iTunes Library" is, in effect, all the music you've imported into iTunes and its associated data and metadata.

By default, this entire collection of information (including the music files themselves), is contained within a FOLDER named "iTunes," and this folder is (again, by default) contained within the user's "Music" folder.

Within the "iTunes" folder, however, are four items: the "Album Artwork" folder; the "iTunes Library" file; the "iTunes Music" folder; and a file called "iTunes Music Library.xml."

This is where the confusion begins. "iTunes" (the computer program), requires an "iTunes LIBRARY" (a term used to convey a concept referring to a collection of data), which data are contained within a FOLDER named "iTunes," which contains a FILE named "iTunes Library," plus another FILE named "iTunes Music Library.xml." Fantastic!

The "iTunes Library" file contains all the non-music, non-artwork information used by iTunes to organize your music collection (including track names, album titles, playlists, ratings, etc.); while the "iTunes Music Library.xml" contains essentially the same information, but is used primarily to exchange information with other programs in the iLife suite (such as iPhoto, iMovie, etc.)

If the "iTunes Library" file becomes lost, damaged, or corrupted, you'll still have all your music and artwork, but iTunes (the program) won't know how to deal with it. Re-importing your music and artwork will restore iTunes functionality, but you will have lost information regarding playlists, ratings, number of times played, etc. If, on the other hand, your music is lost, damaged, or corrupted, it's time to pray that you have a backup of some kind. Same goes for artwork, but to a much lesser extent, since much of it can be downloaded (free) from the iTunes Store (not to be confused with the iTunes Program).

So this is how Apple sets up the iTunes environment by default. If you are content to leave things as they are, everything is likely to be just fine. The problems start when well-meaning users begin to take advantage of various flexibilities that Apple builds into the iTunes program.

The most "dangerous" choice is to UNCHECK the box in "Advanced Preferences" that reads "Copy files to iTunes Music folder when adding to library." Once you do this, every bit of music "added" to your iTunes Library consists solely of POINTERS to the actual music files. If those music files are scattered all over the place, you had best be sure your backup procedure includes backing those files up. Copying your "iTunes" folder or your "iTunes Music" folder (or both) to another drive will succeed in copying ONLY the pointers, NOT the music!

Another somewhat less dangerous choice allowed by Apple is to move the "iTunes Music" folder to a different location. Granted, for large collections (hundreds of GB's), this makes a lot of sense. By dedicating an external drive (or even a network accessible drive) to your music, it is possible to have an enormous collection without using up all the space on your primary drive. In this case, however, you'll need to back up both your "iTunes" folder and your "iTunes Music" folder. Merely backing up your "iTunes" folder will save all your artwork and metadata, but NO MUSIC! Backing up just your "iTunes Music" folder will save your music, but lose your metadata.

So to answer your specific questions, Herman, here's how my little experiment was carried out. My primary drive (which contains OS X and my home folder) goes by the default name of Macintosh HD; the two drives I used we'll call Drive A and Drive B.

Launching iTunes with the option key depressed allowed me to create a new "iTunes LIBRARY" on Drive A. To this LIBRARY, I added the tracks ripped from a single CD, so the track data that the iTunes PROGRAM grabbed from CDDB (the online CD DataBase) got added to the "iTunes Library" FILE within the "iTunes" FOLDER. The music itself got added to the "iTunes Music" FOLDER, also within the "iTunes" folder, and the album artwork (downloaded from the iTunes STORE), was placed into the "Album Artwork" folder, which again, was contained within the "iTunes" folder.

I then quit the iTunes program, and copied the entire "iTunes" FOLDER on Drive A by dragging and dropping onto Drive B. Drive A was then ejected (removed completely from the computing environment), and I relaunched iTunes with the option key depressed. This time, rather than creating a new library, I chose an existing library (the one copied to Drive B), represented in the Finder by the FOLDER on Drive B named "iTunes." Upon selecting this folder I was presented with an iTunes library IDENTICAL to the one I had copied from Drive A.

The reason I did NOT run into the problems you predicted is that although the absolute names of the files on Drive B were different (they were, after all, on Drive B), the relative names were not: everything other than "Drive B" was identical, so iTunes didn't really care. It's kind of like the old days, before Area Codes started multiplying like rabbits. If you wrote down the phone numbers of all your friends in your town, there was no need to write down the Area Code--it didn't matter. But if you travelled around the country collecting phone numbers from people wherever you went, neglecting to write down the Area Codes could lead to serious problems.

And Jpod, to answer your question, I don't think you could do any better than backing up your drive using some kind of drive imaging program. My understanding of these is that you get a bit-for-bit "clone" of your original drive, something impossible to do by means of drag and drop copy. Assuming you keep your backups current, should disaster strike, you merely substitute your "cloned" disc for the original, and your computer is none the wiser. Everything should work exactly as it did with the original disc.

Final disclaimer: I'm a Mac-only guy, and know NOTHING about Windows.
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Thanks for the detailed response, but if I understand what you did the reason iTunes found the songs is not the reason you describe.

I think we agree on this but just to be clear; iTunes stores all new songs in the "music folder" that is established in preferences-advanced-general. By new music I mean music that is ripped by iTunes at the time that folder is in use or a song already ripped and added by dragging and dropping or importing when you have this checked "Copy files to iTunes Music folder when adding to library." If you don't have it checked it will point to to the song location but not copy it into the music folder.

Since you have it checked your songs went into this music folder.

You said "Launching iTunes with the option key depressed allowed me to create a new "iTunes LIBRARY" on Drive A."

Doing so puts the library files on Drive A but does not put the music folder on Drive A unless you go into preferences and change the location to a folder on Drive A. I did not see where you did this.

It does not automatically create a new music folder when you create a new library. The music folder never changes unless you change it in preferences, and if you do it changes it for every library on your computer. That goes for all preferences. They do not apply to just the library in use at the time you change them because there is only one set of preferences and they apply to any library launched by that copy of iTunes.

If I go to preferences in my main library my music folder is currently MusicFour/aug2/

If I launch iTunes with the option key down and create a new library on the drive MusicOne and look at preferences the itunes music folder is still Music4/Aug2. Any new song will be stored in MusicFour/Aug2 and the data stored in the library points to that song on MusicFour/Aug2. Therefore I can move the library files wherever I want because if I launch that library from any location it still points to the song on MusicFour/Aug2

It sounds like this is what you did. To find out do a "get info" on a song in your new library copy on drive B. I bet the song isn't actually stored on Drive B and that is why you can move the library around without losing track of the songs.

BTW your warning to always leave the copy box checked is fine if you have a small library but will not work if your library is too big to hold on a single drive.

Your concept of "relative names" is also off base.

The reason I did NOT run into the problems you predicted is that although the absolute names of the files on Drive B were different (they were, after all, on Drive B), the relative names were not: everything other than "Drive B" was identical, so iTunes didn't really care.

Computers aren't clever enough to go out and find files unless you tell them the exact path. If you move the file from A to B and the pointer says it is in A there is no way it will find it in B.

.

Jethro, I been flogging this here dead horse for days now, and it don't hardly budge none.

Cletus, sometimes them dead horses just enjoy it too damn much. If I wuz you, I'd just stop and see if he don't just git up and gallop off all by hiself.

Sorry, but I've been getting ready for a trip and won't be back till next week, so haven't had time to respond.

The short answer is:

NO

WRONG!

NO

NO

YES IT DOES!

NO THEY DON'T

YES IT DOES!

NO

HUH??

YES IT IS!

READ WHAT I SAID

I AGREE, THIS POINT WAS EXPRESSED POORLY, SORRY.

Don't mean to be a smart ass, but that's all I have time for now!

Cheers!
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There's no way in the world to follow what you wrote, but here's the deal.

I tried it again and it does exactly what I said. I tried it your way and it does not find the song.

Preferences I changed in one library were latched and came up that way in any other library I launched or created.

Creating a new library did not create a new music folder, it stayed the same as what was last set in preferences.

I created a new library with music folder on the same drive
I loaded one song into that library in that music folder
I copied the whole thing to another drive
I deleted the first one
I launched itunes holding the option key and selected the second library
It could not find the song

Why? becuase it was looking on the drive where I deleted it. If I look at the .xml file I see it is pointing at the file I deleted.

The only reason it found your file (I say again) is because you never changed the location on the music folder.

Your description of how iTunes handles music folders on 7-31 is completely wrong as well as just about everything else you have stated,

That is as simple as I can put it. If you still hold on to your other ideas then I can't help you. I don't know what else to tell you other than you are either wrong or you are just screwing with me.