Question about using rsync as a way to backup iTunes library....

[simon lefisch]

Hey everyone,

I have my iTunes library stored locally on my MBP, and I also have a copy of all the media on my 2008 R2 server. Once I start adding more media to my local library, will rsync copy the newly added files to my server or will it try to copy the entire library over again?

 

[I'm a ROb]

Rsync should only copy the new files and the changed files.

Not sure, but I think iTunes changes to files every time you listen to them (to update the 'number of times played' and the 'last played at' fields).

 

[simon lefisch]

Rsync should only copy the new files and the changed files.

Not sure, but I think iTunes changes to files every time you listen to them (to update the 'number of times played' and the 'last played at' fields).

But those changes would be made in the iTunes library file and not the actual media, correct?

If so then that's ok as I keep my iTunes library file sync'd elsewhere. I'm only backing up the media.

 

[grahamperrin]

But those changes would be made in the iTunes library file and not the actual media, correct? …

I assume so. Some file types may be associated with a mixture of metadata data and metadata, but in many (most?) cases the metadata is separate.

So (as you say), a library file.

Plus there may be changes to extended attributes of media files, but I don't know whether the iTunes interface uses those attributes.

 

[simon lefisch]

I assume so. Some file types may be associated with a mixture of metadata, but in many (most?) cases the metadata is separate.

So (as you say), a library file.

Plus there may be changes to extended attributes of media files, but I don't know whether the iTunes interface uses those attributes.

Gotcha.

So most likely (I'm 99.9% sure) all the playback data/favs/etc are stored in the iTunes library file, but if I change any of the ID3 metadata, that would change some of the file attributes so it would have to be re-sync'd. Most of the songs I have are MP3 and I know that info typically carries over with the media itself.

 

[grahamperrin]

Glancing at http://id3.org/ an ID3 tag is "within … file" so if rsync (or whatever you use) does not handle deltas, the sync/backup will be of the file in its entirety.

Looking ahead, I guess that in 2017 there'll be APFS with macOS 10.13 SMB client support for deltas. It's too soon for me to guess whether your 2008 R2 server will lend itself to that combination.

 

[simon lefisch]

Glancing at http://id3.org/ an ID3 tag is "within … file" so if rsync (or whatever you use) does not handle deltas, the sync/backup will be of the file in its entirety.

Awesome, that's what I was looking for. Many thanks for your help

 

[simon lefisch]

@grahamperrin I have created a batch script that will run rsync3 (grabbed the rsync file CCC since it is an updated version [3.0.6] and named it rsync3). When it runs, it seems like it is still transferring all the files, but I cannot be sure. This is the code I have:

rsync3 -rv --progress <source> <destination>

Is this code sufficient to run so it updates any new/modified files without transferring everything?

I did read thru the man but didn't really find anything specific to what I am looking for. Thanks for any help/explanation you can provide.

 

[mfram]

Yes, that should do it. I use '-av' instead of '-rv'. It might not make a difference in your case.

Specifically, I use these commands to copy my iTunes library to a remote server over SSH.

In my case, I'm interested in my music being transferred. Not movies, etc. And my excludes file has stuff like the Podcasts directory.

rsync -av -e ssh --progress --delete --exclude-from=~/Documents/sync-itunes-excludes.dat ~/Music/iTunes/iTunes\ Music server:media/iTunes/
scp ~/Music/iTunes/iTunes\ Music\ Library.xml server:media/iTunes/

cat Documents/sync-itunes-excludes.dat 
iTunes Music/Podcasts/*
iTunes Music/Movies/*

 

[simon lefisch]

Yes, that should do it.

Great, thanks for the response. Much appreciated

 

[grahamperrin]

Likewise, thanks @mfram – it's so long since I used rsync, I didn't know how to answer.

For a short while I wondered why it would be desirable to
( -a ) omit ACLs and extended attributes, then I realised, rsync in BSD-based Darwin differs from rsync in FreeBSD

https://www.freebsd.org/cgi/man.cgi?query=rsync&sektion=1
http://web.archive.org/web/20151203...n/Darwin/Reference/ManPages/man1/rsync.1.html