Read before you go mad! Meraki Non Meraki VPN to Fortigate
So if you are like me and have a bunch of sites with Meraki firewalls connecting back to a Fortigate firewall you may have issues.
All my VPNs bar one 1 IPSec tunnel worked fine.
The one that didn't work would show SA=1 for the phase 2s on the fortigate but ICMP ping traffic only worked for less than a minute and then had no route from the Meraki side and no response was being sent from the Fortigate.
The other way from the local side on the fortigate was sending traffic to the fortigate firewall but had no route after that.
Obviously double checked all Phase 1 and 2 settings and they were identical.
Then I removed the problematic meraki network from the VPN Config section in Meraki, effectively removing the routing.
Then I added it back and restarted the tunnel and voila it works!
So if you you have trouble with meraki to fortigate and all your phase 1 & 2, ipv4 policies are correct then try to remove the problematic network from Non-Meraki VPN peers and add it back after a few minutes.
I got the idea to remove and readd the config because the traceroutes showed no route to the host from the Meraki side.
And yes I did reboot the Meraki appliance several days before to no avail!
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