Just spent a long time troubleshooting a tiny typo in a gre tunnel due to some odd symptoms.
We had 2 machines a,b. machine a is configured properly with a gre tunnel, machine b has its return (or origin ip) typo'd. Traffic is being sent from b to a, but shows in pflog. It looks as if openbsd is already performing a conditional to then dump to pflog instead of blindly sending the traffic back. It would be nice if this condition threw an error in /var/log/messages (gre mismatch) etc or (got x ip, expected y) Thanks
