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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 hostname 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 WSE processes are long lived process, and the ip6tables rules only get loaded 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. 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 up their network with sleeping cat video streams without there being viewers for it. Either way, the TERENA channel already had 100+ subscribers so we were 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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