How to configure IPSEC on Mikrotik?

Question

VPN

Raised VPN on Mikrotik.
Set up everything. eg bozza.ru/art-248.html
The problem is that the tunnel is not established.
In the remote peer, it shows who is trying to connect, and that's it.
Then we will get 789 on the computer
. I tried to register prohibitipsec in the registry, it works, but these are not solutions.
Modem Alcatel, and Mikrotik in DMZ. Could it be because of this?
DMZ Maybe somehow limits ipsec or something else?

Answer 1

Good day! Error 789 is "The wrong type of VPN connection has been selected ." necessary (encryption can simply be turned off). I solved such an error by editing the MTU on the server (Synology DSM) I would also advise you to look at the MTU settings (on the server and client). Also, if the Mikrotik is connected via a modem, then on the modem you need to configure the port forward 1701,500,4500 to the address of the Mikrotik, it is not necessary to put it in the DMZ (by doing this, you open it to the entire Internet).