Editar: terminéusar otra forma de enviar una transmisión de audio a través de la red a una Raspberry Pi remota con Pulseaudio, una que no involucre a Avahi... Así que perdí el interés en esta pregunta; no se moleste en responderla a menos que el problema le resulte extremadamente interesante. Lo dejaré aquí de todos modos, por si mis incursiones iniciales ayudan a alguien.
Estoy configurando una Rapsberry Pi como disipador remoto de Pulseaudio. En otro host en la misma LAN, 'export PULSE_SERVER="[2001:470:ca90:4:ba27:ebff:fee2:ada9]" && mplayer sound.mp3' me permite reproducir música de forma remota; hasta ahora todo bien. También funciona bien en IPv4. El host del cliente es Debian Jessie, el host del servidor es Raspbian Jessie.
Pulseaudio funciona en modo sistema: un disipador sin cabeza es uno de los pocos casos en los que es preferible. Las adiciones a system.pa son las siguientes:
load-module module-native-protocol-tcp auth-ip-acl=127.0.0.1;10.4.0.0/24;2001:470:ca90:4:21b:21ff:feaa:99c9
load-module module-zeroconf-publish
Eliminaré 10.4.0.0/24 una vez que esté en producción, pero por ahora quiero poder realizar pruebas desde cualquier estación en esta subred.
La selección de un receptor Pulseaudio remoto requiere que el avahi del servidor anuncie ese servicio correctamente. Aquí es donde estamos ahora.
Localmente en el servidor host, el servicio Pulseaudio parece anunciarse correctamente:
root@hornwall:~# avahi-browse -a -t
+ eth0 IPv6 pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo PulseAudio Sound Sink local
+ eth0 IPv6 pulse@hornwall: bcm2835 ALSA Analog Stereo PulseAudio Sound Sink local
+ eth0 IPv4 pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo PulseAudio Sound Sink local
+ eth0 IPv4 pulse@hornwall: bcm2835 ALSA Analog Stereo PulseAudio Sound Sink local
+ eth0 IPv6 pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo PulseAudio Sound Source local
+ eth0 IPv4 pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo PulseAudio Sound Source local
+ eth0 IPv6 pulse@hornwall PulseAudio Sound Server local
+ eth0 IPv4 pulse@hornwall PulseAudio Sound Server local
+ eth0 IPv6 hornwall [b8:27:eb:e2:ad:a9] Workstation local
+ eth0 IPv4 hornwall [b8:27:eb:e2:ad:a9] Workstation local
Pero otros hosts en la misma red no ven el servicio Pulseaudio:
root@Kitandara:/etc/pulse# avahi-browse -a -t
+ eth1 IPv6 amour Remote Disk Management local
+ eth1 IPv4 amour Remote Disk Management local
+ eth1 IPv6 amour [54:04:a6:67:9b:53] Workstation local
+ eth1 IPv6 Kitandara [00:1b:21:aa:99:c9] Workstation local
+ eth1 IPv4 amour [54:04:a6:67:9b:53] Workstation local
+ eth1 IPv4 Kitandara [00:1b:21:aa:99:c9] Workstation local
+ eth2 IPv6 Kitandara [00:1b:21:aa:99:cd] Workstation local
+ eth2 IPv4 Kitandara [00:1b:21:aa:99:cd] Workstation local
root@amour:~# avahi-browse -a -t
+ eth0 IPv6 amour Remote Disk Management local
+ eth0 IPv4 amour Remote Disk Management local
+ eth0 IPv6 amour [54:04:a6:67:9b:53] Workstation local
+ eth0 IPv6 Kitandara [00:1b:21:aa:99:c9] Workstation local
+ eth0 IPv4 amour [54:04:a6:67:9b:53] Workstation local
+ eth0 IPv4 Kitandara [00:1b:21:aa:99:c9] Workstation local
root@waga:~# avahi-browse -a -t
+ eth0 IPv6 waga Remote Disk Management local
+ eth0 IPv4 waga Remote Disk Management local
+ eth0 IPv6 waga [54:04:a6:67:9b:b7] Workstation local
+ eth0 IPv4 waga [54:04:a6:67:9b:b7] Workstation local
Esos tres ejemplos son otras estaciones de trabajo. Curiosamente, uno de ellos ni siquiera ve las otras estaciones de trabajo, aunque creo que está configurado de manera similar.
Los cuatro hosts involucrados (Raspberry Pi y cuatro computadoras Intel estándar) están en el mismo segmento Ethernet sin ningún enrutador intermedio. Tanto la conectividad IPv6 como IPv4 están bien. No hay iptables en ninguno de los hosts. Todos esos hosts tienen una configuración Avahi similar, utilizando tanto IPv4 como IPv6 en cualquier interfaz disponible:
root@Kitandara:/etc/pulse# grep -v ^# /etc/avahi/avahi-daemon.conf
[server]
use-ipv4=yes
use-ipv6=yes
ratelimit-interval-usec=1000000
ratelimit-burst=1000
[wide-area]
enable-wide-area=yes
[publish]
[reflector]
[rlimits]
rlimit-core=0
rlimit-data=4194304
rlimit-fsize=0
rlimit-nofile=768
rlimit-stack=4194304
rlimit-nproc=3
Bueno... Ahora estoy estancado: ¿en qué dirección debería presionar?
Por sugerencia de @grawity, aquí hay una idea de lo que pasa a través del éter...
Al escuchar en el eth0 del disipador de Pulseaudio, reiniciar el demonio avahi allí desata una buena ráfaga de los paquetes MDNS esperados:
56 12.938605 2001:470:ca90:4:ba27:ebff:fee2:ada9 -> ff02::fb MDNS 450 Standard query 0x0000 ANY hornwall [b8:27:eb:e2:ad:a9]._workstation._tcp.local, "QM" question ANY pulse@hornwall._pulse-server._tcp.local, "QM" question
57 12.939394 10.4.0.202 -> 224.0.0.251 MDNS 430 Standard query 0x0000 ANY hornwall [b8:27:eb:e2:ad:a9]._workstation._tcp.local, "QM" question ANY pulse@hornwall._pulse-server._tcp.local, "QM" question
58 12.994690 2001:470:ca90:4:ba27:ebff:fee2:ada9 -> ff02::fb MDNS 849 Standard query 0x0000 ANY pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-source._tcp.local, "QM" question ANY pulse@hornwall: bcm2835 ALSA Analog Stereo._pulse-sink._tcp.local, "QM" question
59 12.995632 10.4.0.202 -> 224.0.0.251 MDNS 829 Standard query 0x0000 ANY pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-source._tcp.local, "QM" question ANY pulse@hornwall: bcm2835 ALSA Analog Stereo._pulse-sink._tcp.local, "QM" question
60 13.019775 2001:470:ca90:4:ba27:ebff:fee2:ada9 -> ff02::fb MDNS 652 Standard query 0x0000 ANY pulse@hornwall: bcm2835 ALSA Analog Stereo._pulse-sink._tcp.local, "QM" question ANY pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-sink._tcp.local, "QM" question
61 13.020848 10.4.0.202 -> 224.0.0.251 MDNS 632 Standard query 0x0000 ANY pulse@hornwall: bcm2835 ALSA Analog Stereo._pulse-sink._tcp.local, "QM" question ANY pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-sink._tcp.local, "QM" question
62 13.049454 2001:470:ca90:4:ba27:ebff:fee2:ada9 -> ff02::fb MDNS 738 Standard query 0x0000 ANY pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-sink._tcp.local, "QM" question
63 13.050227 10.4.0.202 -> 224.0.0.251 MDNS 718 Standard query 0x0000 ANY pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-sink._tcp.local, "QM" question
64 13.188819 2001:470:ca90:4:ba27:ebff:fee2:ada9 -> ff02::fb MDNS 450 Standard query 0x0000 ANY hornwall [b8:27:eb:e2:ad:a9]._workstation._tcp.local, "QM" question ANY pulse@hornwall._pulse-server._tcp.local, "QM" question
65 13.189735 10.4.0.202 -> 224.0.0.251 MDNS 430 Standard query 0x0000 ANY hornwall [b8:27:eb:e2:ad:a9]._workstation._tcp.local, "QM" question ANY pulse@hornwall._pulse-server._tcp.local, "QM" question
66 13.245302 2001:470:ca90:4:ba27:ebff:fee2:ada9 -> ff02::fb MDNS 849 Standard query 0x0000 ANY pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-source._tcp.local, "QM" question ANY pulse@hornwall: bcm2835 ALSA Analog Stereo._pulse-sink._tcp.local, "QM" question
67 13.246325 10.4.0.202 -> 224.0.0.251 MDNS 829 Standard query 0x0000 ANY pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-source._tcp.local, "QM" question ANY pulse@hornwall: bcm2835 ALSA Analog Stereo._pulse-sink._tcp.local, "QM" question
68 13.270384 2001:470:ca90:4:ba27:ebff:fee2:ada9 -> ff02::fb MDNS 652 Standard query 0x0000 ANY pulse@hornwall: bcm2835 ALSA Analog Stereo._pulse-sink._tcp.local, "QM" question ANY pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-sink._tcp.local, "QM" question
69 13.271250 10.4.0.202 -> 224.0.0.251 MDNS 632 Standard query 0x0000 ANY pulse@hornwall: bcm2835 ALSA Analog Stereo._pulse-sink._tcp.local, "QM" question ANY pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-sink._tcp.local, "QM" question
70 13.299927 2001:470:ca90:4:ba27:ebff:fee2:ada9 -> ff02::fb MDNS 738 Standard query 0x0000 ANY pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-sink._tcp.local, "QM" question
71 13.300792 10.4.0.202 -> 224.0.0.251 MDNS 718 Standard query 0x0000 ANY pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-sink._tcp.local, "QM" question
72 13.439241 2001:470:ca90:4:ba27:ebff:fee2:ada9 -> ff02::fb MDNS 450 Standard query 0x0000 ANY hornwall [b8:27:eb:e2:ad:a9]._workstation._tcp.local, "QM" question ANY pulse@hornwall._pulse-server._tcp.local, "QM" question
73 13.440068 10.4.0.202 -> 224.0.0.251 MDNS 430 Standard query 0x0000 ANY hornwall [b8:27:eb:e2:ad:a9]._workstation._tcp.local, "QM" question ANY pulse@hornwall._pulse-server._tcp.local, "QM" question
74 13.496557 2001:470:ca90:4:ba27:ebff:fee2:ada9 -> ff02::fb MDNS 849 Standard query 0x0000 ANY pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-source._tcp.local, "QM" question ANY pulse@hornwall: bcm2835 ALSA Analog Stereo._pulse-sink._tcp.local, "QM" question
75 13.497498 10.4.0.202 -> 224.0.0.251 MDNS 829 Standard query 0x0000 ANY pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-source._tcp.local, "QM" question ANY pulse@hornwall: bcm2835 ALSA Analog Stereo._pulse-sink._tcp.local, "QM" question
76 13.521724 2001:470:ca90:4:ba27:ebff:fee2:ada9 -> ff02::fb MDNS 652 Standard query 0x0000 ANY pulse@hornwall: bcm2835 ALSA Analog Stereo._pulse-sink._tcp.local, "QM" question ANY pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-sink._tcp.local, "QM" question
77 13.522523 10.4.0.202 -> 224.0.0.251 MDNS 632 Standard query 0x0000 ANY pulse@hornwall: bcm2835 ALSA Analog Stereo._pulse-sink._tcp.local, "QM" question ANY pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-sink._tcp.local, "QM" question
78 13.551102 2001:470:ca90:4:ba27:ebff:fee2:ada9 -> ff02::fb MDNS 738 Standard query 0x0000 ANY pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-sink._tcp.local, "QM" question
79 13.551881 10.4.0.202 -> 224.0.0.251 MDNS 718 Standard query 0x0000 ANY pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-sink._tcp.local, "QM" question
80 13.640087 10.4.0.202 -> 224.0.0.251 MDNS 243 Standard query response 0x0000 TXT, cache flush PTR hornwall [b8:27:eb:e2:ad:a9]._workstation._tcp.local SRV, cache flush 0 0 9 hornwall.local AAAA, cache flush 2001:470:ca90:4:ba27:ebff:fee2:ada9 A, cache flush 10.4.0.202 PTR _workstation._tcp.local
81 13.641352 2001:470:ca90:4:ba27:ebff:fee2:ada9 -> ff02::fb MDNS 247 Standard query response 0x0000 TXT, cache flush PTR hornwall [b8:27:eb:e2:ad:a9]._workstation._tcp.local SRV, cache flush 0 0 9 hornwall.local AAAA, cache flush 2001:470:ca90:4:ba27:ebff:fee2:ada9 PTR _workstation._tcp.local
82 13.683214 10.4.0.202 -> 224.0.0.251 MDNS 394 Standard query response 0x0000 TXT, cache flush PTR pulse@hornwall._pulse-server._tcp.local SRV, cache flush 0 0 4713 hornwall.local PTR _pulse-server._tcp.local
83 13.684306 2001:470:ca90:4:ba27:ebff:fee2:ada9 -> ff02::fb MDNS 414 Standard query response 0x0000 TXT, cache flush PTR pulse@hornwall._pulse-server._tcp.local SRV, cache flush 0 0 4713 hornwall.local PTR _pulse-server._tcp.local
84 13.700770 10.4.0.202 -> 224.0.0.251 MDNS 849 Standard query response 0x0000 TXT, cache flush PTR pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-source._tcp.local SRV, cache flush 0 0 4713 hornwall.local PTR _pulse-source._tcp.local PTR pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-source._tcp.local PTR pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-source._tcp.local
85 13.702406 2001:470:ca90:4:ba27:ebff:fee2:ada9 -> ff02::fb MDNS 869 Standard query response 0x0000 TXT, cache flush PTR pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-source._tcp.local SRV, cache flush 0 0 4713 hornwall.local PTR _pulse-source._tcp.local PTR pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-source._tcp.local PTR pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-source._tcp.local
86 13.725697 10.4.0.202 -> 224.0.0.251 MDNS 643 Standard query response 0x0000 TXT, cache flush PTR pulse@hornwall: bcm2835 ALSA Analog Stereo._pulse-sink._tcp.local SRV, cache flush 0 0 4713 hornwall.local PTR _pulse-sink._tcp.local PTR pulse@hornwall: bcm2835 ALSA Analog Stereo._pulse-sink._tcp.local
87 13.727151 2001:470:ca90:4:ba27:ebff:fee2:ada9 -> ff02::fb MDNS 663 Standard query response 0x0000 TXT, cache flush PTR pulse@hornwall: bcm2835 ALSA Analog Stereo._pulse-sink._tcp.local SRV, cache flush 0 0 4713 hornwall.local PTR _pulse-sink._tcp.local PTR pulse@hornwall: bcm2835 ALSA Analog Stereo._pulse-sink._tcp.local
88 13.762306 10.4.0.202 -> 224.0.0.251 MDNS 784 Standard query response 0x0000 TXT, cache flush PTR pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-sink._tcp.local SRV, cache flush 0 0 4713 hornwall.local PTR pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-sink._tcp.local
89 13.763689 2001:470:ca90:4:ba27:ebff:fee2:ada9 -> ff02::fb MDNS 804 Standard query response 0x0000 TXT, cache flush PTR pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-sink._tcp.local SRV, cache flush 0 0 4713 hornwall.local PTR pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-sink._tcp.local
90 13.872390 10.4.0.202 -> 224.0.0.251 MDNS 187 Standard query response 0x0000 PTR, cache flush hornwall.local PTR, cache flush hornwall.local
91 13.873522 2001:470:ca90:4:ba27:ebff:fee2:ada9 -> ff02::fb MDNS 174 Standard query response 0x0000 PTR, cache flush hornwall.local
92 13.895013 10.4.0.202 -> 224.0.0.251 MDNS 93 Standard query response 0x0000 HINFO, cache flush ARMV6L LINUX
93 13.895711 2001:470:ca90:4:ba27:ebff:fee2:ada9 -> ff02::fb MDNS 113 Standard query response 0x0000 HINFO, cache flush ARMV6L LINUX
94 14.685743 10.4.0.202 -> 224.0.0.251 MDNS 243 Standard query response 0x0000 TXT, cache flush PTR hornwall [b8:27:eb:e2:ad:a9]._workstation._tcp.local SRV, cache flush 0 0 9 hornwall.local AAAA, cache flush 2001:470:ca90:4:ba27:ebff:fee2:ada9 A, cache flush 10.4.0.202 PTR _workstation._tcp.local
95 14.686990 2001:470:ca90:4:ba27:ebff:fee2:ada9 -> ff02::fb MDNS 247 Standard query response 0x0000 TXT, cache flush PTR hornwall [b8:27:eb:e2:ad:a9]._workstation._tcp.local SRV, cache flush 0 0 9 hornwall.local AAAA, cache flush 2001:470:ca90:4:ba27:ebff:fee2:ada9 PTR _workstation._tcp.local
96 14.727907 10.4.0.202 -> 224.0.0.251 MDNS 394 Standard query response 0x0000 TXT, cache flush PTR pulse@hornwall._pulse-server._tcp.local SRV, cache flush 0 0 4713 hornwall.local PTR _pulse-server._tcp.local
97 14.729184 2001:470:ca90:4:ba27:ebff:fee2:ada9 -> ff02::fb MDNS 414 Standard query response 0x0000 TXT, cache flush PTR pulse@hornwall._pulse-server._tcp.local SRV, cache flush 0 0 4713 hornwall.local PTR _pulse-server._tcp.local
98 14.745767 10.4.0.202 -> 224.0.0.251 MDNS 849 Standard query response 0x0000 TXT, cache flush PTR pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-source._tcp.local SRV, cache flush 0 0 4713 hornwall.local PTR _pulse-source._tcp.local PTR pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-source._tcp.local PTR pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-source._tcp.local
99 14.747376 2001:470:ca90:4:ba27:ebff:fee2:ada9 -> ff02::fb MDNS 869 Standard query response 0x0000 TXT, cache flush PTR pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-source._tcp.local SRV, cache flush 0 0 4713 hornwall.local PTR _pulse-source._tcp.local PTR pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-source._tcp.local PTR pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-source._tcp.local
100 14.769576 10.4.0.202 -> 224.0.0.251 MDNS 629 Standard query response 0x0000 TXT, cache flush SRV, cache flush 0 0 4713 hornwall.local PTR _pulse-sink._tcp.local PTR pulse@hornwall: bcm2835 ALSA Analog Stereo._pulse-sink._tcp.local
101 14.770904 2001:470:ca90:4:ba27:ebff:fee2:ada9 -> ff02::fb MDNS 649 Standard query response 0x0000 TXT, cache flush SRV, cache flush 0 0 4713 hornwall.local PTR _pulse-sink._tcp.local PTR pulse@hornwall: bcm2835 ALSA Analog Stereo._pulse-sink._tcp.local
102 14.807296 10.4.0.202 -> 224.0.0.251 MDNS 841 Standard query response 0x0000 TXT, cache flush PTR pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-sink._tcp.local SRV, cache flush 0 0 4713 hornwall.local PTR pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-sink._tcp.local PTR pulse@hornwall: bcm2835 ALSA Analog Stereo._pulse-sink._tcp.local
103 14.809329 2001:470:ca90:4:ba27:ebff:fee2:ada9 -> ff02::fb MDNS 861 Standard query response 0x0000 TXT, cache flush PTR pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-sink._tcp.local SRV, cache flush 0 0 4713 hornwall.local PTR pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-sink._tcp.local PTR pulse@hornwall: bcm2835 ALSA Analog Stereo._pulse-sink._tcp.local
104 15.917331 10.4.0.202 -> 224.0.0.251 MDNS 231 Standard query response 0x0000 PTR, cache flush hornwall.local A, cache flush 10.4.0.202 PTR, cache flush hornwall.local AAAA, cache flush 2001:470:ca90:4:ba27:ebff:fee2:ada9
105 15.918460 2001:470:ca90:4:ba27:ebff:fee2:ada9 -> ff02::fb MDNS 202 Standard query response 0x0000 PTR, cache flush hornwall.local AAAA, cache flush 2001:470:ca90:4:ba27:ebff:fee2:ada9
106 15.939179 10.4.0.202 -> 224.0.0.251 MDNS 93 Standard query response 0x0000 HINFO, cache flush ARMV6L LINUX
107 15.942478 2001:470:ca90:4:ba27:ebff:fee2:ada9 -> ff02::fb MDNS 113 Standard query response 0x0000 HINFO, cache flush ARMV6L LINUX
108 16.730511 10.4.0.202 -> 224.0.0.251 MDNS 243 Standard query response 0x0000 TXT, cache flush PTR hornwall [b8:27:eb:e2:ad:a9]._workstation._tcp.local SRV, cache flush 0 0 9 hornwall.local AAAA, cache flush 2001:470:ca90:4:ba27:ebff:fee2:ada9 A, cache flush 10.4.0.202 PTR _workstation._tcp.local
109 16.731652 2001:470:ca90:4:ba27:ebff:fee2:ada9 -> ff02::fb MDNS 247 Standard query response 0x0000 TXT, cache flush PTR hornwall [b8:27:eb:e2:ad:a9]._workstation._tcp.local SRV, cache flush 0 0 9 hornwall.local AAAA, cache flush 2001:470:ca90:4:ba27:ebff:fee2:ada9 PTR _workstation._tcp.local
110 16.772372 10.4.0.202 -> 224.0.0.251 MDNS 394 Standard query response 0x0000 TXT, cache flush PTR pulse@hornwall._pulse-server._tcp.local SRV, cache flush 0 0 4713 hornwall.local PTR _pulse-server._tcp.local
111 16.773610 2001:470:ca90:4:ba27:ebff:fee2:ada9 -> ff02::fb MDNS 414 Standard query response 0x0000 TXT, cache flush PTR pulse@hornwall._pulse-server._tcp.local SRV, cache flush 0 0 4713 hornwall.local PTR _pulse-server._tcp.local
112 16.789610 10.4.0.202 -> 224.0.0.251 MDNS 835 Standard query response 0x0000 TXT, cache flush SRV, cache flush 0 0 4713 hornwall.local PTR _pulse-source._tcp.local PTR pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-source._tcp.local PTR pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-source._tcp.local
113 16.791221 2001:470:ca90:4:ba27:ebff:fee2:ada9 -> ff02::fb MDNS 855 Standard query response 0x0000 TXT, cache flush SRV, cache flush 0 0 4713 hornwall.local PTR _pulse-source._tcp.local PTR pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-source._tcp.local PTR pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-source._tcp.local
114 16.814388 10.4.0.202 -> 224.0.0.251 MDNS 714 Standard query response 0x0000 TXT, cache flush SRV, cache flush 0 0 4713 hornwall.local PTR _pulse-sink._tcp.local PTR pulse@hornwall: bcm2835 ALSA Analog Stereo._pulse-sink._tcp.local PTR pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-source._tcp.local
115 16.815894 2001:470:ca90:4:ba27:ebff:fee2:ada9 -> ff02::fb MDNS 734 Standard query response 0x0000 TXT, cache flush SRV, cache flush 0 0 4713 hornwall.local PTR _pulse-sink._tcp.local PTR pulse@hornwall: bcm2835 ALSA Analog Stereo._pulse-sink._tcp.local PTR pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-source._tcp.local
116 16.850830 10.4.0.202 -> 224.0.0.251 MDNS 827 Standard query response 0x0000 TXT, cache flush SRV, cache flush 0 0 4713 hornwall.local PTR pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-sink._tcp.local PTR pulse@hornwall: bcm2835 ALSA Analog Stereo._pulse-sink._tcp.local
117 16.852697 2001:470:ca90:4:ba27:ebff:fee2:ada9 -> ff02::fb MDNS 847 Standard query response 0x0000 TXT, cache flush SRV, cache flush 0 0 4713 hornwall.local PTR pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-sink._tcp.local PTR pulse@hornwall: bcm2835 ALSA Analog Stereo._pulse-sink._tcp.local
118 16.891486 10.4.0.202 -> 224.0.0.251 MDNS 147 Standard query response 0x0000 PTR pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-sink._tcp.local
119 16.892429 2001:470:ca90:4:ba27:ebff:fee2:ada9 -> ff02::fb MDNS 167 Standard query response 0x0000 PTR pulse@hornwall: Sound Blaster X-Fi Go! Pro Analog Stereo._pulse-sink._tcp.local
Los paquetes dirigidos ff02::fb y 224.0.0.251 en el puerto 5353 son justo lo que debería estar sucediendo en teoría, así que eso es bueno.
Pero mientras tanto, ninguna otra estación ha visto nada, ni un solo paquete MDNS.
Unos momentos más tarde en una estación de trabajo:
root@amour:~# tshark -i eth0 -f "port 5353"
1 0.000000 2001:470:ca90:4:21b:21ff:feaa:99c9 -> ff02::fb MDNS 140 Standard query 0x0000 PTR _pulse-sink._tcp.local, "QM" question PTR _non-monitor._sub._pulse-source._tcp.local, "QM" question
2 0.000031 10.4.0.124 -> 224.0.0.251 MDNS 120 Standard query 0x0000 PTR _pulse-sink._tcp.local, "QM" question PTR _non-monitor._sub._pulse-source._tcp.local, "QM" question
Y en el enrutador local:
root@arua:~# tshark -i vlan4 -f "port 5353"
1 0.000000 2001:470:ca90:4:21b:21ff:feaa:99c9 -> ff02::fb MDNS 140 Standard query 0x0000 PTR _pulse-sink._tcp.local, "QM" question PTR _non-monitor._sub._pulse-source._tcp.local, "QM" question
2 0.000135 10.4.0.124 -> 224.0.0.251 MDNS 120 Standard query 0x0000 PTR _pulse-sink._tcp.local, "QM" question PTR _non-monitor._sub._pulse-source._tcp.local, "QM" question
Pero el disipador Pulseaudio anunciado aquí pertenece a otra estación, no a la Raspberry pi que transmitió la gran ráfaga arriba. Si reinicio avahi en esa otra estación de publicidad de fregadero, se ve la ráfaga MDNS correcta en ambos hosts anteriores (amour y arua)... Pero no en la otra estación de trabajo (waga) ni en la Raspberry Pi (hornwall). Esto es extraño porque amour y waga tienen configuraciones extremadamente similares, aunque es posible que algo haya divergido.
Ahora bien, ¿por qué ninguna otra estación ve los paquetes MDNS que parece estar transmitiendo la Raspberry Pi? ¿Por qué sólo dos estaciones ven los paquetes MDNS de publicidad receptora difundidos por la otra estación? ¿Puede haber una mala configuración en el lado receptor?