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The following has taken me an eternity to figure out. I use Airplay from a Linux server to Apple and other airplay devices on my network. Configuring the firewall properly for this to work has not been simple - many guides are vague and lack the specifics needed.
My actual configuration centres around Logitech's squeezeboxserver now known as logitechmediaserver 'LMS' whereby I use the following plugins:
AirPlay bridge - this enables Airplay devices to be used as if they were squeezebox devices, i.e. I can play my LMS stored music / radio / spotify on any of my Airplay devices
ShairTunes2 - this enables Squeezebox devices to be Airplayed to, i.e. I can Airplay from my iPhone/iPad/Mac etc. to any of my LMS squeezebox devices. This is an incarnation of shairplay / shairport .
For along time I have had to disable my firewall to enable my LMS device to connect to my Airplay devices and for music to flow. Once the connection is established I had to then re-enable my firewall - which is not ideal and very cumbersome. Whilst the Airplay devices always showed up in LMS and LMS client the music would just not stream.
Here's how to configure a linux firewall with UFW to enable Airplay:
Linux can receive AirPlay audio using a program called Shairport that I covered over a year ago. Shairplay has since been re-written by the original developer James Laird to no longer rely on perl. The latest version is v1.0-dev here's how to get AirPlay working on Ubuntu using Shairport and iTunes to test it.
UPDATE 2017: THIS ARTICLE IS NOW OUT OF DATE. USE THE SHAIRTUNES2 PLUGIN AVAILABLE IN THE LOGITECHMEDIASERVER PLUGINS PAGE - FOR FIREWALL SETTINGS SEE HERE:
http://confoundedtech.blogspot.co.uk/2018/01/linux-firewall-settings-for-apple.html
This post focuses on playing music from iTunes or iOS devices to a Logitech Squeezebox using AirPlay. The concept is to stream music from iTunes or iOS devices > Ubuntu server > Squeezebox. This requires three key tools Shairport, WaveInput, ecasound and some patience.
Shairport authored by James Laird in 2011 emulates an AirPort Express for the purpose of streaming music from iTunes and compatible iPods. It implements a server for the Apple RAOP protocol, it does not support AirPlay v2 (video and photo streaming). It is a reverse engineer of the RAOP protocol and relies upon the ALAC decoder released by David Hammerton, which is reproduced within Shairport. The project can be found at https://github.com/albertz/shairport
WaveInput authored by BPA is a Logitech Squeezebox plugin that enables PC audio to be captured and played through a Squeezebox. There are version of Windows and Linux and the project can be found here http://code.google.com/p/bpaplugins/
ecasound is a multitrack processing tool for playback, recording, format conversions, effects and mixing. Its use here is to transcode the raw stream from Airplay/Shairport into a format the Squeezebox can understand. I use it to introduce some LAME MP3 compression to the stream to help with my network bandwidth and to reduce playback stutter.
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