TK> 91.155.99.11 is my routers ipv4 address, TK> 216.66.80.90 is the endpoint of the HE tunnel. TK> 2001:0470:1f15:0cb0:0000:0000:0000:0004 is where from I tried to TK> access binkd at 2001:0470:0027:000a:0000:0000:0000:0002
I assume that the router is your end of the 6in4 HE.net tunnel and haproxy is runing on that router too. Is that right?
In this case you would need to insert an INPUT rule before the logdrop: