Problems getting L2TP VPN Connection to work from Ubuntu Server to local Router

[johnquestioneer]

Hi Ubuntu Friends,
I am currently struggling to get a VPN Connection up from a cloud hosted ubuntu VPS to my local Network.
I have tried finding any good guides on how to connect, but all of them fail for me. I want to connect the box to my router (which is running a vpn server using L2TP PSK) and have all of the ubuntus traffic routed exclusively through that tunnel. And also of course have that tunnel start up when the machine restarts.


I have tried it with https://linuxscriptshub.com/configur...n-ubuntu-1604/ this tutorial (which is for 16.04, I am running 20.04 LTS) as well as with this one here https://github.com/jabas06/l2tp-ipsec-vpn-client which is the only one that at least worked "a little". It won't connect but give me the following error when trying to connect

parsed INFORMATIONAL_V1 request 2675422485 [ HASH N(NO_PROP) ]
received NO_PROPOSAL_CHOSEN error notify
establishing connection 'L2TP-PSK' failed

an ike-scan of my routers IP gave me the following output

 Notify message 14 (NO-PROPOSAL-CHOSEN) HDR=(CKY-R=c0879b9d1cd790ba, msgid=a53578d1)

My Router uses 2 Phases for the ipsec authentication

Phase 1: 3des-md5-modp1024!

Phase 2: 3des-md5!

Of which I added the 3des-md5! to the config.
Now I got another problem... When I ty to start the connection again with

sudo ipsec up L2TP-PSK

I get the error

no config named 'L2TP-PSK'

Even though it's configured in my /etc/ipsec.conf...


My config files look exactly like in this github example https://github.com/jabas06/l2tp-ipsec-vpn-client


Also additional questions, my VPN Server has a dynamic IP but I am using a DDNS Service. So I can always connect to it using myname.ddnsservice.net . Can I replace the IPs in the config with domain names? Or how can I do it?


I am completely lost... Grateful for any help!