In the past days, I had some snapclients that were not able to connect to the snapserver. Sometimes only a reboot (of the snapserver host) helped. Now I found out the reason:
It seems that snapclients do not very nicely failover from IPv6 to IPv4. Although I could see an strace (and a log file of my DNS server) that the snapclient was making an AAAA DNS request first, then an A request. But still, connection was not possible unless I configured the IPv4 address literal. So snapclient is preferring IPv6 over IPv4 a bit too much, the connection attempt is done over IPv6 only and your log gets filled with
Dec 05 06:25:09 schlaf snapclient[482]: Resolving host IP for: pidev.example.net
Dec 05 06:25:09 schlaf snapclient[482]: Connecting
Dec 05 06:25:40 schlaf snapclient[482]: Failed to connect to host 'pidev.example.net', error: No route to host
Dec 05 06:25:40 schlaf snapclient[482]: Error: No route to host
Dec 05 06:25:40 schlaf snapclient[482]: Error in socket shutdown: Transport endpoint is not connected
Solution (Workaround?): Configure snapserver to listen on both IPv6 and IPv4 (and not only IPv4 as the default does). Use always
bind_to_address = ::
instead of the default
bind_to_address = 0.0.0.0
Although this is not documented very clearly, the former setting enables both IPv6 and IPv4, while the latter enables only IPv4. See also snapcast bug 518.
In the past days, I had some snapclients that were not able to connect to the snapserver. Sometimes only a reboot (of the snapserver host) helped. Now I found out the reason:
It seems that snapclients do not very nicely failover from IPv6 to IPv4. Although I could see an
strace(and a log file of my DNS server) that the snapclient was making an AAAA DNS request first, then an A request. But still, connection was not possible unless I configured the IPv4 address literal. So snapclient is preferring IPv6 over IPv4 a bit too much, the connection attempt is done over IPv6 only and your log gets filled withSolution (Workaround?): Configure snapserver to listen on both IPv6 and IPv4 (and not only IPv4 as the default does). Use always
instead of the default
Although this is not documented very clearly, the former setting enables both IPv6 and IPv4, while the latter enables only IPv4. See also snapcast bug 518.