IPSEC VPN fortigate

Just like all the VPNs your proposals and things all need to match. What appliances are you using? UTM, SG, XG? Fortinet appliance details?

UTM 9 and Fortinet FG60D

This is info from fortinet side the guys give me, I try to match those parameters and vpn don't connect.

IKE:

encryption AES256

SHA

dh group 2

lifetime 28800

preshared key

IPSec:

AES 256

SHA

PFS group 2

lifetime 3600

UTM 9 and Fortinet FG60D

This is info from fortinet side the guys give me, I try to match those parameters and vpn don't connect.

IKE:

encryption AES256

SHA

dh group 2

lifetime 28800

preshared key

IPSec:

AES 256

SHA

PFS group 2

lifetime 3600

Salut and welcome to the UTM Community!

Based on the above, you would want:

However, depending on your hardware there might be a better choice like "AES 128 PFS."

Confirm that both sides have DPD enabled and that they have selected Main Mode, not Aggressive.

If that doesn't get you connected, disable debug (!), disable the IPsec Connection, start the IPsec Live Log, wait for it to show 10 lines, enable the IPsec Connection and show us the lines from startup to failure - probably less than 60 lines.

Cheers - Bob