I'm having the same issue as described at http://forums.juniper.net/t5/Routing/GRE-routing-issue/td-p/287911 (EX4550 running 14.1X53-D25.2)
Has anyone succeeded to route traffic through GRE in EX4200/EX4500 series? I've been trying it for days with no success.
Feel free to share any ideas or possible solutions.
Thank you.