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See http://www.wowza.com/forums/showthread.php?37909-PushPublishRTMP-doesn-t-work-with-IPv6 on how to do that.

The RTMP push out to YouTube is done to two host names (a.rtmp.youtube.com and b.rtmp.youtube.com). Initially I had put these hostnames in my ip6tables configuration, but eventually the cam went offline. Turns out that the IP addresses are not stable - which is perfectly valid. But because the ip6tables rules only get loaded and thus resolved at boot time, eventually the rtmp.youtube.com host names would start resolving to something else, and the outgoing stream would get blocked by the ip6tables script. Since there is no such thing as "Google IP ACL" I had to open up outgoing TCP port 1755 to the entire Internet. Not a big deal, but something to keep in mind.

Gotchas

• YouTube Live is only be available on channels that have at least 100 subscribers. I'm guessing that this is done by YouTube to prevent random users to clog from clogging up their network with sleeping cat video webcam streams without there being any viewers for it. Either way, the TERENA YouTube channel already had 100+ subscribers so we were all good to go.
• YouTube Live is not available to users in Germany: http://en.wikipedia.org/wiki/Blocking_of_YouTube_videos_in_Germany. This is a political issue that we can't solve.

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