Hi
so I have IKEv2 + GRE working between a CHR and a Fortigate in tunnel mode and from the Fortigate I can ping the IP of the loopback bridge which was created on the Mikrotik but vice versa, from the Mikrotik I can't ping the corresponding IP of the tunnel interface of the Fortigate. Pings are allowed and rules are in place on the Fortigate. If I only allow GRE traffic from the Forti to the Tik, GRE tunnel gets connected immediately. If I only allow the other way, from the Tik to the Forti, the tunnel stays down.
It seems to me that the Mikrotik is missing a route or someting and can't initate a connection to the IP of the Fortigate.
Where to look? Any NAT/masquerade exceptions to make on the Mikrotik?
Various firewall rules are in place but it still doesn't work if I put "allow all" rules on top of the chains.
I can post the whole config of both sides, or just let me know which parts could be interesting.
Thanks!