A coworker has found a way to share audio over network for No Machine in multinode environments, specifically to applications that are executed in remote servers (not the node) through exporting X (like an ssh -X).
Imagine you have the next scenario:
NX Terminal Server –> NX Node –> Your virtual Environment (desktop) –> Remote App «Call an application from a remote server» (which requires audio enabled) with ssh -X or export the X server variable.
The main documents of No Machine for audio settings are:
But, those documents do not explain how pulse works, or how you should set it up in order to work with NX.
Setting up Audio with NX
- Enable each user to run an instance of Pulse in the node
- Enable the network support for audio in Pulse Server (NX)
- Export the Pulse variable to the remote X execution so it uses the enabled pulse server instance.
Running pulse in the nodes
My coworker designed an script for this purpose:
root@TESTNOMACHINENODE1:~# cat /usr/local/bin/custom_pulseaudio dir=$HOME/.pulse_server disp=$(echo $DISPLAY | cut -d":" -f2) let snd=5000+$disp sed -i "s/%port%/$snd/g" $PULSE_SCRIPT echo $HOSTNAME:$snd > $PWD/.pulse_server /usr/bin/pulseaudio $@
This will be called from /usr/NX/etc/node.cfg (in each node must be enabled)
# # Specify path and name of the command to start PulseAudio server. # CommandStartPulseAudio "/usr/local/bin/custom_pulseaudio"
When a user is authenticated it will run an instance of pulse audio in the node.
Enable pulse audio support over network
Inside the product, when you are using a multinode environment you’ll have a sort of embbed pulse server configuration in:
In here you can enable several modules like the xkbbell module. But, to enable audio over network you must enable the module-native-protocol-tcp functionality of pulse server:
### Load several protocols ### Network access (may be configured with paprefs, so leave this commented ### here if you plan to use paprefs) #load-module module-esound-protocol-tcp #load-module module-native-protocol-tcp load-module module-native-protocol-tcp auth-anonymous=1 port=%port%
Export the Pulse variable to the remote X
We call an application using ssh, for example (we have keys not using a password):
(Assuming you know which node you’ve landed, i.e: MY_PULSE_SERVERTESTNOMACHINENODE1:7001)
With the DISPLAY variable we export the display of the current user in the node.
ssh -o StrictHostKeyChecking=no $REMOTE_SERVER "export PULSE_SERVER=$MY_PULSE_SERVER; export DISPLAY=$DISPLAY; google-chrome"
as you can see, we are not using ssh -X (you could) but we are only exporting the DISPLAY variable and the PULSE_SERVER variables.
Pulse audio isn’t required to be installed in the destination server.