Good morning all, I have a question about chromecast audios [https://www.whathifi.com/google/chromecast-audio/review] and their operation on an IPv6-only mostly LAN. Several months ago, following the great tutorial Ondřej Caletka from the RIPE NCC did and then the talk Jen Linkova did in Tuesday's plenary at RIPE87 in Rome, I deployed a new Vlan in my home network to test the use of option 108 etc. It worked a treat to the point where I believed I'd tested any potential corner cases and so a few weeks back I transitioned to deploying it on my main home network vlan. Once again I thought everything worked a treat and got no complaints until recent days when my wife tried to stream some music to an old chromecast audio device we use to connect to some wired ceiling speakers. Having looked into the issue it would appear that the chromecast audio can't/won't do v6 and this is something that caught me on the hop a little. Those devices that are dual-stacked continue to see and can make use of this chromecast audio but those devices that are happily working away and utilising the option 108 to not have v4 (such as my wife's mobile device) can no longer see/communicate with the chromecast. I guess my question out of all of this is if any of you have run up against this particular problem and if so what was your solution. I suppose in theory it doesn't need to be a chromecast, I guess any device that's unable or unwilling to use v6. How have you managed direct communications between two devices on the same LAN segment whereby one device is doing v6 only and the other refuses to use v6 and will only use v4? I'd dearly love to avoid having to turn off option 108 on the main network. Thanks, -- Mick O’Donovan Senior Network Engineer HEAnet CLG Ireland's National Education and Research Network 3rd Floor, North Dock 2 | 93/94 North Wall Quay | Dublin D01 V8Y6 | Ireland +353 1 6609040 | mick.odonovan@heanet.ie | www.heanet.ie Registered in Ireland, No. 275301 | CRA No. 20036270