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Hi,
I'm reading the Mitaka installation guide. I've seen that the GRE 
tunneling mechanism isn't mentioned anymore (it was at least until Kilo).
What happened to GRE ? is it not usable anymore in Mitaka, or what ?

I've a Kilo production IaaS using GRE and I need to migrate it to 
Mitaka; do I have any chance to maintain GRE ?

thanks,

     Alvise