I am facing an issues with setting up a Meraki L2TP VPN connection from my Fedora 32 KDE Edition. We use a Pre-shared Key and not a certificate. Windows, Mac and Android devices connect just fine.

I have the following IPsec Settings:
- Enabled IPsec tunnel to L2TP host
- Enter Pre-shared key we set on our MX64
- Phase 1: 3des-sha1-modp2048
- Phase 2: 3des-sha1
- Unchecked "Enforce UDP encapsulation

The following PPP Settings:
- Checked only PAP authentication method
- Checked the following Compressions:
-- Allow BSD compression
-- Allow Deflate compression
-- Allow TCP header compression
-- Use protocol field compression negotiation
-- Use Address/Control compression
- Set MRU to 1400
- Set MTU to 1400

When I try to establish a VPN connection to my Meraki MX64 I get the following event log:
Sep 3 08:06:59 Non-Meraki / Client VPN negotiation msg: phase1 negotiation failed.
Sep 3 08:06:59 Non-Meraki / Client VPN negotiation msg: failed to pre-process ph1 packet (side: 1, status 1).
Sep 3 08:06:59 Non-Meraki / Client VPN negotiation msg: failed to get valid proposal.
Sep 3 08:06:59 Non-Meraki / Client VPN negotiation msg: no suitable proposal found.
Sep 3 08:06:55 Non-Meraki / Client VPN negotiation msg: phase1 negotiation failed.

Does anybody setup successfully a Meraki L2TP VPN connection on Fedora?

Try using

- Phase 1: - Phase 2:

Just did still getting the following

Sep 3 09:37:01 Non-Meraki / Client VPN negotiation msg: failed to pre-process ph1 packet (side: 1, status 1).
Sep 3 09:37:01 Non-Meraki / Client VPN negotiation msg: failed to get valid proposal.
Sep 3 09:37:01 Non-Meraki / Client VPN negotiation msg: no suitable proposal found.
Sep 3 09:36:59 Non-Meraki / Client VPN negotiation msg: phase1 negotiation failed.

Try using MSCHAPv2 only with Point-to-Point Encryption (MPPE) and allow stateful encryption with all other options unchecked.

Sorry but I get the same errors

Do you have a firewall on your system?