Just finished playing with my new toy an iPhone 4S, and mostly because I couldn’t find anything about setting up wireless sync across different LANs on google I’ve published this.

First of all you need a *NIX based router between your different LANs, in my case I used Ubuntu 11.04 but this also works on OpenWRT.

First of all install avahi-daemon, for Ubuntu

sudo apt-get install avahi-daemon

or OpenWRT

opkg install avahi-daemon

Next you need to configure avahi to act as reflector, you need to set at least the following varibles in /etc/avahi/avahi-daemon.conf

enable-wide-area=yes
enable-reflector=yes

You might also want to set

allow-interfaces=ethX,ethY
deny-interfaces=ethZ

Then all you need to do is restart the avahi-daemon and then iTunes should then find your phone.

Update – This works much more reliably with iOS 5.1