This post is a bit different from my previous posts, but I thought it was interesting enough to post, and it might help someone in the future.
The issue at hand is to get music onto my iPhone 4 running iOS 6, using only a Linux machine. Unfortunately, the iTunesDB on the phone is encrypted on iPhone 4 and up, and the excellent libgpod team have not been able to reverse-engineer it yet, so USB syncing of music is not possible natively on Linux. From this there are two obvious workarounds: jailbreak your phone, and use some of the programs available on Cydia to enable adding music to the iTunesDB, or somehow get your iPhone talking with a real iTunes installation.
I chose the second option, but iTunes does not work very well on wine currently, so I chose to install windows on a virtual machine. I had a Windows 7 OEM license bundled with the laptop, so I set up Virtual Machine Manager and Qemu, and installed iTunes on top of this. This works very well with the RedHat virtIO drivers for networking and virtual storage, highly recommended.
To allow the iTunes on my virtual machine to see my music stored on my linux box, I set up a Samba share, restricted to the virtual network. iTunes 11 no longer has the option to add an entire folder to your library from the menu, but you can still drag and drop folders from Windows Explorer into iTunes, which took a while, but worked.
I was able to get USB passtrough to the virtual machine working for a short while, long enough to get the iPhone recognised in iTunes, but this was painfully slow. I ticked the box for enabling wifi sync in iTunes, and left it for the next day.
The wifi sync feature requires a Bonjour connection between iTunes and the iPhone, but unfortunately Bonjour cannot bridge from the virtual machine over virtIO, and the other virtual network devices I tried did not work well. Finally, i found mdns-repeater a small program that does exactly what I want: it runs on my Linux machine, and forwards Bonjour packets from the virtual network between the host and virtual machine, and the wireless network on which my iPhone and Linux host are both connected. Using this, iTunes and the iPhone can see each other, and I am syncing with around 10 Mbit/s, much faster and more reliably than with the USB passtrough solution.
If anyone finds this useful, feel free to ask questions if you need a step or two fleshed out. I’ll be happy to help. 🙂