Please help. How to set up IPsec VPN XAUTH PSK on Ubuntu?

Question

VPN

Good day to all!

It is not possible to set up a vpn server on ubuntu, so that it works directly from the router. I insisted on Libreswan, when connected from windows everything works.
The router has limited capabilities, but it is still expensive to change. Supports only IPsec VPN XAUTH PSK, ie. without certificates and L2TP. And even XAUTH is optional.
I'm tinkering for the third day.
Gives timeout.
In addition to the server IP, PSK, login and password in the router settings, you need to enter IPsec ID - Key ID, as I understand it, this is a group ID - added to ipsec.conf. And the local address of the VPN network - also already tried everything.
Help, I really need it to work :)

Answer 1

Have you already studied the examples from the shwan site? There's a crappy cart of examples for all occasions. XAUTH is not often used - is it impossible to use a regular PSK?

Answer 2

My yesterday's reply disappeared somewhere.

What does Ubuntu have to do with it if the VPN client is running on the router?

ubuntu-server. Router is a client. Router Fritz!Box.

Have you already studied the examples from the shwan site? There's a crappy cart of examples for all occasions.

Carefully studied - re-read once again. It turned out that the group name in ipsec.conf had to be enclosed in square brackets.
So the issue is resolved :)
Thank you all :)